Core Privacy Policy
private. essential. Core...
Go-to Android apps. No third‑party ads. No tracking. No accounts. No AI inside.
Who is responsible: Core Products & Services, LLC, a Texas limited liability company, United States. Mailing address: c/o Registered Agents Inc., 5900 Balcones Dr, Ste 100, Austin, TX 78731-4298, USA.
Privacy contact: gotocorepstx@gmail.com. Core does not have a data protection officer, because the law does not require one for what Core does.
Effective date: November 2, 2026
Applies to: Core Cycle, Core Gallery, Core Games, Core Music, Core Notes, Core Scan, Core Sign, Core Utilities, Core Weather, Core Workout, and Trio Live Wallpapers for Android.
The short version
- Core apps have no accounts, no ads, and no tracking. Core does not sell your information.
- Core gathers and keeps no data through its apps. What you enter stays on your device and under your control: you can see it, export it where the app offers an export, and delete it.
- Core Cycle has no internet access. What you log stays on your device, encrypted, and Core cannot see it, so Core has nothing to hand over if someone asks. Core Cycle is for ages 13 and over. (Section 15)
- Core Music, Core Weather and Core Utilities use the internet only for the things their own sections describe. Core Music's Google Cast switch is off until you turn it on. (Sections 18, 23, 22)
- The only information that reaches Core is Google Play's statistics and records for downloads and purchases, and what you choose to send (emails, and crash reports you choose to send). (Section 6)
- Core Cycle, Core Gallery, Core Notes, Core Scan, Core Sign, and Core Utilities open where you left off, and you choose how long you can be away before the app lock asks again. (Section 4)
- To ask about your information, email gotocorepstx@gmail.com. We reply within one month. (Section 8)
Contents
- What privacy means
- Purchases in all Core apps
- Rate or share pop-up
- Where you left off, and the app lock
- Children
- Information Core itself receives
- What Core does not have or do
- Your rights
- Legal requests
- Security
- This website and where information is processed
- Your choices
- Changes to this policy
- Disclaimers
- Core Cycle
- Core Gallery
- Core Games
- Core Music
- Core Notes
- Core Scan
- Core Sign
- Core Utilities
- Core Weather
- Core Workout
- Trio Live Wallpapers
1. What privacy means
Privacy, as used in this policy, refers to the practices Core Products & Services, LLC does not undertake. Beyond the promises above, there are no analytics, no profiles, no cloud, no Core servers, and no social features. Core does not operate an anonymizing service. Encryption is used only where a section below says so: the Core Cycle database and backups, the Core Gallery vault, the Core Sign vault, everything Core Notes stores, and the FTP connections you save in Core Utilities. Core Weather, Core Music, Core Utilities, and Google Play purchases are the only things that use the internet, each described in its own section. Core Cycle has no internet access of its own; only Android's Google Play Store app, for purchases, uses it for Core Cycle. In Core Music, the optional Google Cast switch also uses your local Wi-Fi network, and if you turn it on, Google's own Cast library collects anonymous usage data for Google, not for Core (see section 18).
2. Purchases in all Core apps
Every Core purchase is completed or facilitated through Google Play. Google Play processes the payment and decides refunds. Core does not receive your card details, and Core does not issue a separate license you can hand to another person. Prices are in U.S. dollars and are shown on Google Play before you buy.
3. Rate or share pop-up
Core Gallery, Core Games, Core Notes, Core Scan, Core Sign, Core Weather, Core Workout, and Trio Live Wallpapers can show a "Rate or share" pop-up now and then. It appears no sooner than 90 days after you install the app, and only after you have opened the app on at least 5 different days. After that, it appears at most once every 90 days. Core Scan also waits until you have saved a scan, Core Sign until you have exported a document, and Core Workout until you have finished a workout. Core Games shows it only on its home screen, never during a game.
- What stays on your device: to decide when to show the pop-up, the app keeps a few dates and counts (such as when it last showed the pop-up, the days you opened the app, and, where it applies, how many workouts you have finished) in its private storage. They are never sent anywhere and are not copied to your Google backup.
- Rate on Google Play: opens the app's page in Android's Google Play Store app, or in your browser if the Play Store app can't open it. A rating or review you choose to leave there is handled by Google Play under Google's policies.
- Share: opens Android's share menu with a short message and the app's Google Play link. Nothing is sent unless you pick an app and send it yourself, and that app's own policy then applies.
- Not now: closes the pop-up, as do Back and tapping outside it.
The app itself sends nothing. The pop-up is built into each app and does not use Google Play's in-app review service.
4. Where you left off, and the app lock
Core Cycle, Core Gallery, Core Notes, Core Scan, Core Sign, and Core Utilities open where you left off. If you leave one of these apps and come back, you are on the same screen. If Android closed the app in the background to free memory, it opens again on the screen you were on. These apps do not send you back to their home screen on their own.
To do this, the app gives Android a short note about where you were. Android keeps that note in your device's memory, and Core never receives it. It holds only the place, never the contents: no note text, no entries, no scans, photos, or document contents, no search words, no PINs or keys, and nothing from a Vault. Android clears the note when you swipe the app away from your recent apps, force stop it, or restart your device, and the app then starts from its home screen. Android describes this here: https://developer.android.com/topic/libraries/architecture/saving-states
- Core Cycle: which tab is open, the day you had open to edit, and the month and day selected in the calendar. Not what you logged for them.
- Core Gallery: the tab, the albums, groups, and pages you had opened (by name and ID), the picture or video you had open (by ID), and how far you had scrolled. The Hidden view and the Vault are never kept, and neither are search words.
- Core Notes: the tab, the folder, and the ID of the note you had open, never its title or text. After you unlock, the note opens again from the encrypted database.
- Core Scan: the tab and the step you were on (camera, review, or crop, with the page number). The pages of an unfinished scan are kept separately, as described in section 20.
- Core Sign: the screen and tab, the folder, and, for a document that is not in the Vault, which document it is, its page, and whether Reader mode was on. A Vault document is never named: Core Sign opens on the Vault screen, locked.
- Core Utilities: which page or tool is open, not what you typed, measured, or picked. A tool opens in its starting state.
App lock. Core Cycle and Core Notes have an app lock with a PIN or pattern you set (and, if you turn it on, a strong biometric). Core Gallery's Lock on close uses your device's screen lock. Core Sign has the same timing for its Vault. In Settings you choose how long you can be away before the app asks again: Immediately, or 1, 5, 10, 15, or 60 minutes. The default is 10 minutes. Core Cycle and Core Notes also offer Once a day, which keeps the app unlocked until midnight.
- The time is counted from when you leave the app. When it has passed, the lock screen covers the screen you were on, and after you unlock you are right where you left off.
- Immediately asks again each time you come back. In Core Cycle and Core Notes, a return within 10 seconds does not ask again.
- Whether the app is locked is kept only in memory, never on disk. An app that starts fresh always asks first.
- Leaving always protects the most sensitive parts, whatever time you choose. Core Gallery's Vault locks whenever you leave it. In Core Sign, the decrypted working copy of a Vault document is removed whenever you leave the app. If you come back within the time you chose, the document opens again; if not, the Vault is locked.
- Core Cycle and Core Notes only ask if you have set a lock. Without one, what you store is still encrypted on the device, but anyone holding your unlocked device can open it.
The recent-apps preview and screenshots. Core Cycle and Core Notes hide their screens from the recent-apps preview and from screenshots by default, and you can change this in each app's Settings.
5. Children
Core apps are general-audience apps. They are not made for children, and they have no accounts, profiles, chat, or social features. Core does not knowingly collect personal information from children. Core Utilities is meant for ages 16 and up because of the M-Lab speed test. Core Cycle is meant for ages 13 and over. Some countries require parent consent before an online service can rely on a young person's consent to collect their data. Core Cycle does not receive your information, so it does not ask anyone for consent. If you are under 18, you may want to talk to a parent or another adult you trust about using any health app. Core does not knowingly receive information from children under 13: if you think a child has sent us personal information, for example in an email, write to us and we will delete it.
6. Information Core itself receives
Core's apps do not send your information to Core. Core does not collect anything beyond Google Play's statistics and records for downloads and purchases, and what a person chooses to send us, such as an email or a crash log. Core has no profiles, no servers, and nothing else. Core does not want to know your personal information. The only information that reaches Core is what is listed here.
- Emails you send us, including crash reports you choose to send. Your email address, your message, and anything you attach. Most Core apps (all except Core Games, which keeps no crash log) have a crash report button that opens Android's share menu with our address filled in. Nothing is sent unless you finish sending it yourself. A report holds technical details of the fault, as each app's section describes (for example the error trace, the app version, the device maker and model, and the Android version), and not what you entered in the app. We use emails and reports to answer you and to find and fix faults. We keep them only as long as needed to do that, and to meet legal and tax obligations.
- Google Play download and purchase statistics and records. Google Play gives Core download and purchase statistics and records for orders; Google's own policy covers what Google collects. When you buy an unlock, Google Play handles the payment and shows Core a record of the order, such as the order number, the item, the price and the date. Google Play also lets Core look up an order by the buyer's email address (Google's help page: https://support.google.com/googleplay/android-developer/answer/2741495 ). Core does not receive your card details. We use these records to confirm a purchase, to handle refunds, and to keep accounts and tax records. We keep them only as long as needed for that, and as Google Play and tax law require.
Core has no accounts, no mailing list, no advertising or analytics tools, and no servers that receive data from the apps. Core's email is a Gmail address, so emails to Core are held by Google (Gmail) under Google's privacy policy.
Why Core may use this information (people in the EEA and the United Kingdom). For emails and crash reports, Core's legitimate interest in answering the people who write to us and in fixing faults, or your consent when you choose to send a report. For purchase records, to carry out your purchase, to meet legal duties such as tax records, and Core's legitimate interest in handling refunds and keeping accounts. Core does not receive the health information you enter in Core Cycle, so it does not rely on consent or any other legal basis to process it. If that ever changed, Core would tell you first and ask for your explicit consent before receiving it.
7. What Core does not have or do
- No accounts or sign-in. There is no account, so there is nothing to anonymize.
- No wearables or health platforms. Core apps do not connect to wearables, and Core Cycle does not use Health Connect.
- No ad or tracking partners. No ads, no advertising ID, no analytics or tracking tools, and no marketing tools from Core. Two libraries from Google are described in the sections they affect: Google Play Billing's own diagnostics, and, only while Core Music's Google Cast switch is on, Google's Cast library (section 18). Core receives none of it.
- No community. No chat, forums, profiles, or social features.
- No sharing with partners. Core does not share information with partners, researchers, employers, insurers, or anyone else, and does not sell it. Nothing is received from the apps that could be shared.
- No marketing messages. Core does not send marketing messages of any kind, by email or inside the apps. Core has no mailing list.
- No service providers for app data. No one processes information from the apps for Core. For emails, Core uses Google (Gmail).
8. Your rights
Wherever you live, you can ask Core to tell you what personal information it holds about you, to correct it, to delete it, to limit how it is used, to give you a copy you can move, or to stop using it, and you can take back any consent you gave. If you are in the EEA or the United Kingdom, these rights come from the GDPR and the UK GDPR, and you can also complain to your data protection authority (in the UK, the Information Commissioner's Office at https://ico.org.uk/make-a-complaint/ ; in the EU, the list of authorities is at https://www.edpb.europa.eu/about-edpb/about-edpb/members_en ).
How this works for the apps. What you enter in Core's apps is on your device, not with Core. There is nothing for Core to look up, change, export or delete, and Core cannot identify anyone from it. Core does not collect extra information about you just to be able to answer a request about it (Article 11 of the GDPR). You do all of it yourself, in the app:
- See it: it is in the app on your device.
- Export it: where an app offers an export or backup, you start it yourself. For example, Core Cycle can export your days as a CSV file (a plain, unencrypted file that you save where you choose; you confirm first) or make an encrypted backup. Core Notes and other apps describe theirs in their own sections.
- Delete it: delete entries in the app, use Erase all data in Core Cycle, or clear the app's storage or uninstall the app in Android settings. Files you saved yourself stay until you delete them.
What Core can provide. Core does not collect anything beyond Google Play's statistics and records for downloads and purchases, and what a person chooses to send us, such as an email or a crash log. Core has no profiles, no servers, and nothing else, and does not want to know your personal information. So for a request about your data, Core can only provide what it actually holds: that Google Play information, and any emails or crash logs you sent.
How to ask about what Core does hold (the list in section 6): email gotocorepstx@gmail.com. We reply within one month. If we need longer, we tell you before the month ends and say why. It is free, unless a request is clearly baseless or repeated.
Proving who you are. Core does not ask for ID or for any health information. For a request about an email or a purchase, we may ask you to write from the same email address or to give the order number.
If we say no, you can reply to ask us to look again. You can also contact your data protection authority or your state attorney general.
United States. Core does not sell your personal information, and does not use it for advertising. State laws such as those of California, Washington, Nevada and Connecticut give residents rights over their personal information. For what Core holds, these rights work as described above. For Core Cycle's health information, see the consumer health data notice in section 15.
9. Legal requests
If a court, police, a government agency or anyone else asks Core for your information, Core can only provide what it actually holds. Core does not collect anything beyond Google Play's statistics and records for downloads and purchases, and any emails or crash logs a person chose to send. Core has no profiles, no servers, and nothing else, and does not want to know your personal information. In particular, Core does not hold what you log in Core Cycle: it is on your device, Core cannot open your device, and Core does not have the password or recovery code for your encrypted backups. What Core holds is limited to the list in section 6.
10. Security
Core keeps your information safe mainly by not having it: Core Cycle's entries stay on your device, encrypted (see section 15, Encryption). Core's own records (emails, crash reports, purchase records) are kept with Google (Gmail and Google Play) and are protected by Google's security. No security measure is perfect, and encryption on your device does not help if someone else can unlock your device. If you find a security problem in a Core app, email gotocorepstx@gmail.com with "Security" in the subject. If Core ever lost information it holds about you, it would tell you as the law requires.
11. This website and where information is processed
This website. This page is hosted by Cloudflare Pages. Cloudflare says it logs visitors' IP addresses for security and to operate its network. Core sets no cookies and runs no analytics or advertising tools on this page, and does not see Cloudflare's logs.
Where information is processed. Core does not move your information between countries, because Core's apps send Core nothing. The few records Core holds (section 6) are kept by Google (Gmail and Google Play), which may process information in the United States and other countries. Google Play (for purchases) and, only when you turn it on in Core Music, Google Cast, are run by Google, which may process information in the United States and other countries under its own policies and legal safeguards: https://policies.google.com/privacy and https://policies.google.com/privacy/frameworks .
12. Your choices
- Cycle: use the app lock (PIN, pattern, or fingerprint) and choose how long it waits before asking again (section 4), keep "Hide screenshots and the recent-apps preview" on (it is on by default), leave reminder details off (the default) so reminders say only "Reminder," choose the plain Tools icon if you do not want your home screen to mention cycles, make an encrypted backup and keep the backup password or recovery code somewhere safe, and use Erase all data when you want everything removed.
- Gallery: turn on "Strip location when sharing," use the app lock and choose how long it waits before asking again (section 4), and send the crash log only if you choose.
- Games: turn off sound, haptics, or keep screen on in Settings, play the three free games without buying anything, and use Restore purchase if you reinstall.
- Music: leave the Artwork lookup, Lyrics lookup, and Google Cast switches off, do not send the crash log, or turn off Android backup.
- Notes: use the app lock and choose how long it waits before asking again (section 4), keep "Hide in Recents and screenshots" on (it is on by default), skip calendar import or deny calendar permission (.ics import still works), share a crash report only if you choose, leave Show alarms over other apps off (the default) or revoke Display over other apps in Android settings at any time, and keep your backup password or recovery code somewhere safe.
- Scan: leave text recognition off if you don't need searchable PDFs. Saved scans in Documents › Core Scanned Documents are not encrypted, so delete the ones you no longer need. You can also send sensitive documents to Core Sign and keep them in its Vault (a Core Sign paid feature).
- Sign: keep signatures and sensitive documents in the Vault, choose how long the Vault stays open after you leave (section 4), remember that exported files are not encrypted, and choose Copy rather than Link when you don't want Core Sign to be able to change or delete the original.
- Utilities: leave Network tools off, use SFTP rather than plain FTP for File Share and the FTP client, and stop Wi-Fi File Share when you are done.
- Weather: type a place instead of using Detect location, turn off location permission, or turn off alerts and notifications.
- Workout: turn off vibration, lower or mute cue volume, or skip the optional battery-optimization exemption. Use Backup only if you want a file copy of saved workouts.
- Trio Live Wallpapers: use Hidden Mode to keep saved wallpapers out of other apps, and share the crash log only if you choose.
- All apps: uninstalling an app or clearing its storage removes the data it keeps on your device. Changes you saved to your own files stay. For Cycle, all entries are deleted unless you saved an encrypted backup. For Gallery and Sign, Vault contents are deleted; for Games, saved games and best scores are deleted, because Core Games has no backup; for Notes, all notes are deleted unless you made a backup. For Cycle, the time the trial started can remain in Android backup. For Music and Workout, the trial start date can remain in Android backup and Google Play services Block Store (see each app's section).
- Questions or requests: email gotocorepstx@gmail.com (see section 8). Core keeps nothing from the apps on its own servers, so most questions are about what is stored on your device.
13. Changes to this policy
Core has no accounts or mailing list, so it cannot email you about changes. When this policy changes, the effective date at the top changes, and material changes are also noted in the release notes of the app concerned. Core reviews this policy at least once a year, and whenever an app's behavior changes.
14. Disclaimers
Each app has its own Disclaimers screen. The disclaimers are separate and are not part of this privacy policy.
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15. Core Cycle
Core Cycle is a cycle tracking app for Android from Core Products & Services, LLC. It is a record-keeping and calculation tool: it stores what you enter and shows estimates worked out only from your own entries. It is not a medical device, it does not give medical advice, and it is not contraception. No account is required. Core Cycle is meant for ages 13 and over (see section 5).
Your health information
What you log in Core Cycle (period days, flow, symptoms, moods, notes, and the dates they belong to) is health information, and Core treats it with extra care. It stays on your device. Core Products & Services, LLC does not receive it, cannot see it, does not sell it or share it, and does not use it for ads, profiles, or analytics. The only ways your entries leave your device are the ones you start yourself: an encrypted backup, a CSV export, or something you share (see What leaves your device). Core Cycle does not use Health Connect, and it does not request location, contacts, camera, microphone, or device-calendar access. For what Core Cycle does not have (no account, no wearable import, no ads or tracking partners, no sharing with partners, no messages from Core), see section 7.
No internet
Core Cycle does not request Android's internet permission, so the app cannot connect to the internet. Your entries are not uploaded anywhere by Core Cycle. Core Cycle has no ads, no analytics, and no crash-reporting SDK. Android's Google Play Store app checks your Google Play purchase when you unlock Core Cycle and each time you come back to it. If that check can't run, Core Cycle keeps the last result it saved on your device, so you are not locked out.
What stays on your device
- Your entries: for each day you log, whether it was a period day, the flow, symptoms (the built-in ones and any you add yourself), moods, and a note. They are kept in an encrypted database in the app's private storage.
- Your settings for estimates and reminders: such as your usual cycle and period length, whether the optional fertile window is on (it is off by default), reminder choices, cycles you excluded, a pause on estimates, the first day of the week, and the order of your symptom buttons. They are kept in the same encrypted database.
- Your trial and purchase record: the time your 45-day trial started, a few counters that stop a changed device clock from extending the trial, and the last result of your Google Play purchase check, in the encrypted database. The trial start time is also kept in one small separate file (see Android backup).
- Where you were: which tab is open, the day you had open to edit, and the month and day selected in the calendar, as a short note that Android keeps on your device so Core Cycle can open where you left off (see section 4). It holds none of your entries.
- Your keys: the data key that opens the database is protected by the Android keystore and by your PIN or pattern (see Encryption). Core cannot recover it.
- Reminder schedule (not encrypted): if you turn reminders on, the times of the next reminders, whether the daily reminder is on and its time, and whether reminder details are on are kept in a small file outside the encrypted database, so reminders can fire while the app is locked. Reminder times follow your estimated dates.
- App settings (not encrypted): such as the lock timing, whether screenshots are hidden, the color theme (Mauve, Dark, Mist, or Blush), whether the calendar shows a grid, whether the Home and Calendar drag bars are open, and how far you got in first-run set-up. They are kept in a small settings file because they must be read before the database opens. The launcher icon you choose is stored by Android.
- First-run answers: the first time you set up Core Cycle, your answers (last period date, earlier periods, cycle and period length, and your fertile window and reminder choices) wait in that settings file until the encrypted database opens. Then they are moved into the database and deleted from the file. A backup or CSV file you pick during set-up is held only in memory until then.
- A crash log: the last 5 crashes, kept in the app's private storage: the app version, the device maker and model, the Android version, the time, the error type, the first 200 characters of the error message, and the stack trace. Core Cycle does not add your entries to it. It stays on your device unless you share it (see What leaves your device).
- How long it is kept: your entries stay on your device until you delete them, use Erase all data, or uninstall the app. Core does not keep a copy. Android backup keeps only the time your trial started, in your Google account; Google decides how long it keeps that backup. Three trial numbers (when it started, how much of it is used, and the time of the last update) are also kept in Google Play services on this device only, with no cloud copy. The crash log keeps the last 5 crashes. Files you save yourself (backups and CSV exports) stay until you delete them.
Erase all data (in Settings, confirmed twice) deletes your entries, settings, keys, and reminders from the device. It keeps the time your trial started, so erasing does not restart the trial. Encrypted backups and files you exported are not affected. Uninstalling Core Cycle or clearing its storage also deletes your entries, unless you saved an encrypted backup.
Encryption
- Database: encrypted with SQLCipher (AES-256), using a key created on your device.
- Key protection: the data key is wrapped by a key in the Android keystore and, when you set an app lock, also by your PIN or pattern (PBKDF2-HMAC-SHA256, 600,000 iterations). You can also unlock with a strong biometric if you turn it on: Android checks it on the device, and Core never sees or stores your biometric data. Your PIN or pattern always works too. They cannot be recovered by Core or anyone else. If you forget them and have no backup, your entries cannot be opened. When Core Cycle locks, the key is cleared from memory and the database is closed. You choose when it locks again after you leave (see section 4).
- Backups: encrypted with AES-256-GCM, using a key made from your backup password or recovery code (see Backups, import, and export).
- Not encrypted: CSV files you export, anything you share to another app, the reminder schedule and app settings described above, and, if you turn on reminder details, the reminder text ("Period expected soon," "Log today," or "Estimated fertile window") that Android shows in the notification, including on the lock screen.
- Screen protection: by default Core Cycle hides its screens from screenshots and from the recent-apps preview. You can turn this off in Settings.
Reminders
Reminders are optional. They use Android's inexact alarms, so they can arrive a few minutes late. By default a reminder shows only "Core Cycle" and "Reminder." If you choose the plain Tools launcher icon, reminders show that name and "Reminder" instead, and reminder details are not shown. Android may still show the name Core Cycle in your device's app settings and in the header of a reminder, and Core Cycle cannot change that. Reminders are set up again after a restart, a time or time zone change, or an app update.
Android backup
Android backup is turned on for Core Cycle, but only for one small file: the time your 45-day trial started. Your entries, settings, database, and keys are left out by explicit backup rules, for both cloud backup and device-to-device transfer. This is so reinstalling Core Cycle does not restart the trial. A restored start time can only shorten the trial, never extend it. Google runs that backup, not Core, and Core never receives the file. Google says Auto Backup keeps app data in your Google Drive and, on Android 9 and newer, end-to-end encrypts it using your device's PIN, pattern, or password. You can turn it off in Android's backup settings. To move your entries to a new device, use a Core Cycle encrypted backup.
Backups, import, and export
- Encrypted backup (.corecycle): saved where you choose with Android's file picker. It holds your logged days (dates, flow, symptoms, moods, notes), the symptoms you added, and your cycle and reminder settings. It does not hold your lock, keys, trial, or purchase result. It is encrypted with AES-256-GCM using a key made from a separate backup password you set (at least 8 characters, with letters and numbers) or from a one-time recovery code. If you lose both, nobody can open it. Core Cycle can remind you to make a backup (every 30 days by default). Core does not upload backups.
- CSV export: a spreadsheet file of your days (date, period day, flow, symptoms, moods, note), saved where you choose. It is plain, unencrypted CSV text (UTF-8), so anyone who has the file can read it. Core Cycle shows a warning, and you confirm before the file is made. It is never created unless you start it, and Core Cycle does not send it anywhere.
- Import: you can import a Core Cycle CSV file, a CSV file in the format published by drip, or a Core Cycle backup, from a file you choose, during first-run set-up or later in Settings. Core Cycle reads it on your device, does not change the file, and tells you how many rows it skipped. Core Cycle is not affiliated with drip.
What leaves your device
Only what you send yourself, plus purchase checks and the one small backed-up file described above. Core Cycle sends nothing itself.
- Backups and exports: saved where you choose with Android's file picker. After that, where the file goes is up to you and the app or service that holds it.
- Crash report (optional): after a crash, a Crash report button appears on the lock screen. It shows the last crash, and Share crash report opens Android's share menu with our email address filled in. Nothing is sent unless you finish sending it.
- Privacy policy: tapping Privacy policy in Settings opens this page in your browser.
- Purchase: Android's Google Play Store app handles the purchase and checks it with Google Play. Google's privacy policy applies to those checks.
Third parties
None are contacted by Core Cycle. Google Play Billing handles the optional unlock, and Google's Android backup, which Google runs and Core does not, can hold the trial start time.
Consumer health data notice (Washington, Nevada, and Connecticut)
Some U.S. states have laws about "consumer health data," which can include information about reproductive or sexual health, bodily functions, and symptoms. They include Washington's My Health My Data Act (chapter 19.373 of the Revised Code of Washington), Nevada's consumer health data law (Senate Bill 370 of 2023, sections 603A.400 to 603A.550 of the Nevada Revised Statutes), and Connecticut's consumer health data provisions (sections 42-515 to 42-526 of the Connecticut General Statutes). What you log in Core Cycle can be that kind of information. This notice says how Core Cycle handles it.
- What it covers: the dates you mark as period days, flow, symptoms, moods, notes, and the cycle and reminder settings you choose, plus the estimates (such as when your next period may start) that Core Cycle works out from your entries on your device.
- Where it comes from: only from you. Core Cycle does not get it from anyone else.
- Where it stays: on your device. Core Products & Services, LLC does not receive it, copy it, or keep it, and has no servers that could. Core Cycle has no internet permission. The only copies that exist elsewhere are files you create yourself (an encrypted backup or a CSV export) and keep where you choose.
- Why it is used: only to show your calendar, history, estimates, and reminders, and to make the backups and exports you ask for. It is not used for ads, profiles, analytics, research, or anything else.
- Sharing and selling: none. Core does not share or sell it, no third party or affiliate receives it from Core Cycle, and no third party collects it through Core Cycle over time or across other websites or apps.
- Service providers: none. No one processes it for Core.
- Your choices: because the data is on your device, you control it there. You can see, change, and delete any entry in the app, export a copy as a CSV file, erase everything with Erase all data, or uninstall the app. Core Cycle does not ask you to agree to collection because Core does not receive your information. If that ever changed, this notice would be updated first, and Core would ask for your consent before collecting, using, or sharing any additional category of this information or using it for any additional purpose.
- Requests and appeals: you can also email gotocorepstx@gmail.com to ask whether Core holds any of your Core Cycle information, to see it, to ask for it to be deleted, or to appeal an answer you disagree with. Core holds none, so the answer will be that there is nothing to look up, change, or delete, and that your entries are in the app on your device (see also section 8). You can also contact your state's Attorney General.
- The laws: Washington, chapter 19.373 RCW: https://app.leg.wa.gov/rcw/default.aspx?cite=19.373&full=true . Nevada, NRS 603A.400 to 603A.550: https://www.leg.state.nv.us/division/legal/lawlibrary/Nrs/NRS-603A.html . Connecticut, sections 42-515 to 42-526: https://www.cga.ct.gov/2025/pub/chap_743jj.htm
- Changes: if this notice changes, the effective date at the top of this policy changes, and the change is also noted in the Core Cycle release notes (see section 13).
Permissions
- Notifications: asked the first time you turn on a reminder (Android 13 and newer).
- Run at startup: to set reminders up again after a restart, a time change, or an app update.
- Vibration: for feedback on the PIN pad and pattern. It needs no prompt.
- Biometric (optional): only if you turn on biometric unlock. Android checks it on the device, and the app only receives a yes or no.
- Google Play billing: for the optional unlock.
- Not requested: internet, network state, advertising ID, location, contacts, camera, microphone, storage, calendar, exact alarms, foreground services, full-screen alerts, or Health Connect.
Purchases
Core Cycle is free to try for 45 days with every feature. The 45 days are counted on your device. After that, everything you logged stays on your device to view, edit, delete, and export, and adding new entries needs a $9.99 one-time unlock through Google Play Billing. No subscription. Google handles the payment, and Core receives no card details. The unlock stays associated with the Google Account that bought it, and Restore purchase checks it again on a new or reinstalled device. (Payment, refund and card terms common to all apps are in section 2.)
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16. Core Gallery
Core Gallery is a paid app ($2.99, no trial) for viewing and organizing photos and videos on the device. Its vault is encrypted. The rest of the app is not. It has no accounts.
No internet
Core Gallery does not request Android's internet permission, so the app cannot connect to the internet. Your photos are not uploaded anywhere by Core Gallery, and editing and enhancing happen on the device. The first time you open Core Gallery, Android's Google Play Store app checks your Google Play purchase, so that first start needs a connection.
What stays on your device
- Your settings: albums (a new album you create is kept only as a name here until you first move or copy something into it), groups, pins, hidden albums, sort and filter options, local favorites and tags, widget options, and app lock.
- Thumbnails of your photos and videos, kept in Core Gallery's private files folder and marked so other apps, galleries, and photo pickers don't list them, plus an image cache in the app's cache.
- A list of your library, so Core Gallery opens quickly. Vault items are never in this list or in the thumbnails.
- Where you were: the tab, the albums, groups, and pages you had opened, the picture or video you had open, and how far you had scrolled, as a short note that Android keeps on your device so Core Gallery can open where you left off (see section 4). The Hidden view, the Vault, and search words are never in it.
- SVG thumbnails in the grid are rendered on the device and cached in Core Gallery's private app storage. They are never uploaded.
- Startup and scroll timing, kept only in Core Gallery's on-device diagnostic log. It is never sent anywhere.
- Small preview copies of the photos shown in your home-screen widgets, kept in the app's private files folder and marked so other apps' galleries don't list them. They are deleted when you remove the widget.
- The apps you choose for "open with" or editing, so it can open them again next time.
- A crash log, kept in the app's private storage (the last 5 crashes). It holds the error trace, the app version, the device model, the Android version, and memory numbers: how much memory Core Gallery was using and its limit, counts of its running tasks, of the photos in its library and in its saved and search lists, whether an accessibility service was on, the size and file type of the largest picture being opened, and counts of thumbnails that couldn't be made, by file type. It never includes file names, paths, photo data, or location.
- After a crash, the next start skips restoring the last screen and offers to share the crash log. Nothing is sent automatically.
- Changes you choose to make, like edits, rotation, info/EXIF edits, and deletes, are saved to your own photo and video files through Android.
- When photos or videos are added to or removed from your device, Core Gallery can update its library and make new thumbnails in the background. This happens on the device, and nothing is sent.
- Android backup is turned off for Core Gallery. Thumbnails, widget previews, the library list, and the Vault are also left out when Android moves app data to a new device.
Vault
You can move photos and videos into Core Gallery's Vault. The vault is encrypted with AES-256-GCM. The key stays in the Android keystore and is wrapped by a PIN or a 9-dot pattern you set, or by a strong biometric if you turn it on. Biometric unlock is optional: Android checks it on the device, and Core never sees or stores your biometric data. Your PIN or pattern always works too. Files in the vault are not in the normal photo library and do not show in the Files app. Leaving the vault locks it. Moving a picture out returns it to the album it came from. Vault videos can't be opened in other apps, to keep them private.
- Vault files are not backed up. If you uninstall Core Gallery or clear its data, Vault files are permanently deleted. Move anything you want to keep back out of the Vault first.
Photo location
- Core Gallery does not use your device's GPS and does not request location permission.
- It asks for Android's media location permission so it can read location data already saved inside your photos (EXIF), for example to show or edit a photo's info.
- An optional setting, Strip location when sharing, removes location data from photos before you share them. It is off by default and works on photos, not videos.
- Shrink video (optional, offered when you share or select videos) makes a smaller copy on the device, saved to Movies/Core Gallery. The copy never carries location data, whatever the Strip location setting is. Your original video is only read, never changed.
What leaves your device
Only what you send yourself, plus one check: when you first open Core Gallery, Android's Google Play Store app confirms your purchase with Google Play. Core Gallery sends nothing itself; Google's privacy policy applies to that check. The crash log stays on your device unless you choose to send it: Settings › About › Crash log opens Android's share menu with our email address filled in, and nothing is sent unless you finish sending it. When you share, set a wallpaper, or open a photo or video in another app, Android sends that file to the app you pick. That app's own privacy policy then applies.
- Vectorize (images only): sends the picture you chose to Core Utilities on the same device, through Android, so it can be traced there. The first time, Core Gallery explains this before anything is sent. If Core Utilities is not installed, Core Gallery opens its Google Play page instead.
- Choosing a photo for another app: when another app asks you to pick a photo, Core Gallery returns only the photo you choose to that app.
Third parties
Core Gallery contacts no third parties itself. Google Play handles the purchase, and Android's Google Play Store app checks it with Google Play when you first open the app.
Permissions
- Photos and videos (all or selected): to show your library. The Downloads album shows only what is in your device's main Download folder.
- Media location: to read location data stored in your photos (see above).
- Set wallpaper: only when you choose to set one.
- Biometric (optional): only if you turn on biometric unlock for the Vault.
- Google Play license check: so Android's Google Play Store app can confirm your purchase.
- Folder access (optional): if you tap "Allow Gallery to read this folder" in Zips, Android's folder picker lets Core Gallery read the zip files in the folder you choose.
- Media management (optional): if you allow it in Android settings, Core Gallery can move, trash, or delete your photos and videos without asking each time. It only acts on files you choose in the app.
- Run at startup, wake lock, and a short background task: added by Android's task scheduler so on-device work (such as widget updates and thumbnails for new photos and videos) can finish. Nothing is sent anywhere.
Purchases
Core Gallery is $2.99 with no trial, paid on Google Play. The app has no in-app purchases.
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17. Core Games
Core Games is a set of 12 classic games for Android: 2048, Brick Smash, Card Match, Checkers, Chess, Dots & Boxes, Fox Hop, Gem Match, Reversi, Row Rush, Snake, and Sudoku. No account is required. Games with a computer opponent run it on the device, and every game works offline.
No internet
Core Games does not request Android's internet permission, so the app cannot connect to the internet. Your scores and saved games are not uploaded anywhere by Core Games. All 12 games, including the computer opponents, run on the device. Android's Google Play Store app checks your Google Play purchase whenever Core Games opens. If it can't, Core Games keeps the last result it saved on this device, and the free games work either way. After a reinstall, the other games unlock again the next time Google Play can confirm your purchase. Core Games has no crash-reporting SDK.
What stays on your device
- Your settings: accent color, sound, haptics, keep screen on, the launcher icon you choose, and each game's own options, kept in the app's private storage.
- One saved game for each game, so a game you stop picks up where you left it.
- Your three best scores for each game and mode, with dates, and counts of games played and won. Brick Smash has no top three; it keeps its own record, next.
- Brick Smash progress: the highest level you have reached (shared by Easy, Medium, and Hard), and for each of the three difficulties, your stars and your best score for every level.
- A local record of whether the one-time unlock is active, so the unlock still shows when you are offline.
- A few dates and counts for the "Rate or share" pop-up (see section 3).
- Core Games has no export, import, or account sync. Android backup is turned off for Core Games, and its data is also left out when Android moves app data to a new device. Uninstalling Core Games or clearing its storage deletes your saved games, scores, and settings.
What leaves your device
Only what you send yourself, plus purchase checks. Android's Google Play Store app handles the purchase and confirms it with Google Play. Core Games sends nothing itself, and Google's privacy policy applies to those checks. Core Games collects no analytics and keeps no crash log.
- Rate on Google Play and Share: as described in section 3. Nothing is sent unless you choose it.
- Privacy policy: tapping Privacy policy in Settings opens this page in your browser.
Third parties
None are contacted by Core Games. Core Games does not use Google Play Games services: there is no sign-in, no leaderboard, no achievements, and no cloud saves. Your scores and saved games stay on this device. Google Play Billing handles the optional unlock.
Permissions
No permissions to grant. The install-time permission is Google Play billing, used for the unlock. Sound is made on the device, haptics and keep screen on use Android's own view settings, and none of them needs a permission. Core Games does not request internet, location, camera, microphone, contacts, storage, or notifications.
Purchases
Core Games is free to install. Checkers, Fox Hop, and Reversi are free to play. A $5.99 one-time unlock through Google Play Billing opens the other 9 games. Google handles the payment, and Core receives no card details. No trial. No subscription. The unlock stays associated with the Google Account that bought it, and Restore purchase checks it again on a new or reinstalled device. (Payment, refund and card terms common to all apps are in section 2.)
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18. Core Music
Core Music is a mobile-first music library manager and HiFi player. Playback uses the files on your device. It does not stream from the internet, and it has no cloud library. If you turn on the optional Google Cast switch, it can also play your files on a Cast speaker or display on your Wi-Fi (see Google Cast below). No account is required. A network connection is not required.*
What stays on your device
- Your library index (track list, tags, folders), playlists, ratings, hearts, play settings, and EQ, kept in the app's private storage.
- Album art the app saves for your library.
- A small activity log, kept in the app's cache. It stays on the device unless you send it (see below).
- A crash log of the last 5 crashes, kept in the app's private storage: the error trace, the app version, the device model, and the Android version. File paths, URIs, coordinates, and media file names are removed. It stays on the device unless you choose to share it.
- Changes you make on purpose, like editing tags, saving cover art, or saving playlists, are written to your own music files or folders. Core Music also saves a ratings backup playlist (
CoreMusic-Ratings.m3u8) about once a day, in your playlist folder or in app storage. It adds.nomediafiles so its artwork does not show up in gallery apps.
Android backup
Android backup is turned on for Core Music. Android Auto Backup can include Music settings, EQ, the library index, ratings, hearts, the Network Features switches, your trial start date, and your unlock status. It does not include your music files or cached art and waveforms. Google runs that backup, not Core. You can turn it off in Android's backup settings.
Core Music saves the date your 14-day trial started in the app's private storage on this device. Android backup and Google Play services Block Store keep a copy for you. Block Store copies it to your Google backup only when Google can end-to-end encrypt it. That way, clearing data or reinstalling usually doesn't restart the trial. Google runs these, not Core; Core never receives the date.
What leaves your device
*A connection is optional. Core Music has three Network Features switches in Settings: Artwork lookup, Lyrics lookup, and Google Cast. All three start off, and nothing is looked up and no Cast device is searched for until you turn one on. Library and playback work offline. Core Music has no crash-reporting SDK of its own and no update check. Google Play's billing library may send its own diagnostic data to Google, and, only while Google Cast is on, Google's Cast library may too, and neither you nor Core can opt out of that while Google Cast is on (see Google Cast below). Core receives none of it.
Those lookups work like this:
- Lyrics lookup (off until you turn it on): the song title, artist, album, and length (or the text you type) go to LRCLIB (lrclib.net). You choose the lyrics before they are saved.
- Artwork lookup (off until you turn it on): the album and artist names go to MusicBrainz (musicbrainz.org) to find the matching release, and the cover is then downloaded from the Cover Art Archive (coverartarchive.org). You choose the image before it is saved.
These services see your IP address and the search words needed to find a match.
- Sending a crash log (optional): tapping "Send Crash Log" opens Android's share menu with the log file attached and an email address filled in. Nothing is sent unless you finish sending it in the app you choose. The log can include app activity, error details, and timestamps.
- Sharing the crash log (optional): after a crash, or from the Crash log in Settings, Share crash log opens Android's share menu with the crash log and our email address filled in. Nothing is sent unless you finish sending it.
- Your device's media controls: like other music players, Core Music shares the current track's title, artist, and artwork with Android's media controls, the lock screen, and any connected devices you use, such as Bluetooth or Android Auto. If you cast, it also gives that information to the Cast device you choose (see Google Cast below).
Google Cast (optional, off by default)
Core Music has a Google Cast switch in Settings, under Network Features. It starts off. While it is off, Core Music does not start Google's Cast library, does not search for Cast devices, shows no Cast button, and does not run the local server described below. When you turn it on, a Cast button appears in the top bar at the top right. Casting needs Google Play services on your device. Turning the switch off takes full effect the next time Core Music starts.
- What it does: you pick a Cast speaker or display on your Wi-Fi network, and your music plays there instead of on your device. Core Music does not mirror or cast your screen. Core Music uses Google's Default Media Receiver, a receiver app that Google hosts.
- Local server: so the Cast device can fetch the songs and album art you cast, Core Music runs a small web server on your device, only while you are casting. It is reachable only on your local network, and its addresses include a random code made for each casting session. The link between your device and the Cast device is plain HTTP on your own network, so it is not encrypted. Anyone on your Wi-Fi who learns an address during a session could play that stream.
- What goes to the Cast device: the music itself, plus the title, artist, album, and album art of the tracks you cast. Google's list of audio formats Cast supports gives FLAC up to 96 kHz and 24-bit, so Core Music lowers the resolution of higher-resolution tracks on your device before sending them, and changes formats Cast cannot play into one it can. Playback on your own device is not changed.
- What Google's Cast library may collect: Google's page for the Cast Android SDK says the library collects information about its interactions with Cast devices (app activity), and that portions of it go to a Google log collection server. It says the information logged includes generic discovery events, session management events, mobile device information, and client Cast app information. Google says it collects this anonymously, that the logs contain no identifiers that can be traced to a specific user, that the data is encrypted in transit and kept for a short time before being aggregated, and that the library does not transfer or share it with third parties or with other apps on your device. Google also says that neither the app developer nor the user can opt out of this collection or delete the data. Core does not receive it. This happens only while the Google Cast switch is on: if the switch is off when Core Music starts, Core Music does not start the library, so nothing is sent. Core Music cannot shut the library down while the app is running, so if you turn the switch off after using it, turning it off takes full effect the next time Core Music starts. The only way to prevent it is to keep the Google Cast switch off. Source: https://developers.google.com/cast/docs/android_sender/data_disclosure
- What your Cast device may send to Google: Google says its Chromecast and Cast devices may collect system activity, crash reports, and usage data, including the apps and domains you cast. Crash reports and diagnostics are optional and are controlled in the Google Home app. Google says it does not collect the specific content being played, although a media service partner may. Makers of other Cast-enabled devices may collect other information under their own privacy policies. Sources: https://support.google.com/chromecast/answer/6076570 and https://support.google.com/chromecast/answer/9001232
- Notifications on other devices: Google says that while you cast, other Android devices on the same Wi-Fi network can get a media control notification. It shows the name of the casting device, the content provider, and controls such as pause and stop. Each person can turn these off in their Android settings, and the owner of a Cast device can turn them off in the Google Home app. Sources: https://support.google.com/googlecast/answer/7206638 and https://developers.google.com/cast/docs/android_sender/integrate
- Google's policies apply: Cast runs through Google Play services and Google's Cast library, and Google's Privacy Policy and Google Cast terms apply to what Google does. Core Music does not use the Cast library to send anything to Core.
Third parties
LRCLIB, MusicBrainz, and the Cover Art Archive, only when the matching switch is on and you start a lookup. Only while Google Cast is on and you cast: Google Play services and Google's Cast library, Google's Default Media Receiver, and the Cast device you choose. Google Play Billing handles the purchase. Google Play services Block Store keeps a copy of the trial start date (see above).
Permissions
- Music and video files / storage, and folders you pick: to find and play your files. Core Music can only reach the folders you choose with Android's folder picker.
- Internet and network state: only for the optional lookups, Google Cast, and Google Play Billing.
- Local network (Google Cast, optional): while you cast, Core Music and your Cast device talk to each other over your Wi-Fi. Core Music asks you for no extra permission for this on the Android versions it supports today.
- Notifications and foreground services: for playback controls, library scanning, and keeping Cast playback running.
- Audio settings and wake lock: for EQ and output, and to keep playback running with the screen off.
- Battery optimization exemption (asked, optional): so playback and scans aren't stopped.
- USB host (optional feature): for USB audio devices (DACs).
- Google Play billing: for the unlock.
Purchases
Core Music offers a 14-day free trial, then a one-time $4.99 unlock through Google Play Billing. Google calls this kind of purchase a non-consumable one-time product: it is a single charge, it does not renew, and once bought it stays associated with the Google Account that bought it. Signing in on another device with the same Google Account is how the unlock is recognized again. Google's own terms allow a transfer between Google Accounts only when you own both accounts and Google has turned that transfer on for Play. (Payment, refund and card terms common to all apps are in section 2.)
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19. Core Notes
Core Notes is a notes, calendar, and reminders app for Android: Encrypted Notes, Calendar, & Reminders. It supports text, checklist, photo, drawing, and audio notes, reminders, a calendar, a Clock with alarms, and widgets. No account is required. Everything Core Notes stores is encrypted on the device.
PDF attachments: PDFs you attach to a note are copied into Core Notes and stored encrypted on your device, the same way as your notes and images. They are never uploaded. When you export or share an attachment, Core Notes creates a decrypted copy and hands it to the app or location you choose; that copy is no longer protected by Core Notes.
Crash reports: if Core Notes crashes, it saves the error trace (no note text) to its private storage only, and can show it on a startup or lock screen with a Share button. Nothing is sent automatically. Share fills in our support address (gotocorepstx@gmail.com) and the subject Core Notes crash log; nothing is sent until you send it, and you can change or remove the address first.
No internet
Core Notes does not request Android's internet permission, so the app cannot connect to the internet. It has no crash-reporting SDK and does not fetch link previews.
What stays on your device
- Your notes, checklists, labels, colors, reminders, calendar events (including events you import), reminder locations, reminder notes, and settings, in an encrypted database in the app's private storage.
- Photos, drawings, and audio recordings you add, as encrypted files in the app's private storage.
- A small preview image of each note's card, so Home can show it quickly. It is stored encrypted in the app's private storage and deleted with the note.
- Crash reports from the last 5 crashes: the error, where in the app it happened, the app version, the device model, and the Android version. They contain no note text, and they stay on the device unless you share them.
- A schedule of alarm times, kept outside the encrypted database so reminders can fire while the app is locked. It holds no note text, and no reminder titles unless you turn on note titles in reminders; if you do, those titles are also stored outside encryption.
- Clock alarm times, repeat days, sounds, and the timer, kept outside the encrypted database so they ring while the app is locked. Alarm labels and your world clock cities are stored encrypted. The world clock uses the time zones built into Android, with no internet or location access.
- Where you were: the tab, the folder, and the ID of the note you had open (never its title or text), as a short note that Android keeps on your device so Core Notes can open where you left off (see section 4). After you unlock, the note opens again from the encrypted database.
- Android backup is turned off for Core Notes.
Encryption
- The database is encrypted with SQLCipher (AES-256), including the search index, reminders, and calendar events.
- Photos, drawings, and audio are encrypted with AES-256-GCM, including audio while it is recording.
- The key is created on your device and protected by the Android keystore. With an app lock, it is also protected by your PIN or pattern, or a strong biometric. When Core Notes locks, the key is cleared from memory and the database is closed. The key is never sent anywhere, and Core cannot recover it.
- Backups are encrypted, password-protected zip files. The backup password is separate from your app lock (at least 8 characters, with letters and numbers), and a recovery code can open the backup instead. Backups include notes, reminders, calendar events, and your Core Notes settings (theme, reminder defaults, widget, and list settings). App-lock settings, your PIN, pattern, and keys are never included. If both the password and the recovery code are lost, the backup cannot be opened, by us or anyone.
- Widgets and reminder notifications hide content while the app is locked.
- Screen protection: by default Core Notes shows a blank card in the recent-apps preview and blocks screenshots and screen recording of the app. You can turn this off in Settings.
- Not encrypted: notes you export as text, Markdown, PDF, image, or Word files, calendars you export as .ics files, anything you share to another app or copy to the clipboard, and the alarm schedule (including reminder titles, if you turn them on). Text you copy is cleared from the clipboard after 60 seconds if Clear copied text is on (the default).
Calendar import (optional, part of the unlock)
- From your device's calendars: only when you tap Import calendar, Core Notes asks for permission to read your device's calendars. This reads the calendars Android already keeps on the device, such as those synced by Google, Samsung, or Exchange accounts. You pick the calendars and the date range. The events are copied once into Core Notes' encrypted database; you can re-import later by hand. Core Notes never writes to, changes, or deletes your device's calendars, and it never syncs in the background.
- From an .ics file: opening or choosing an .ics file copies its events into Core Notes. The event title becomes the reminder name, the start and end become the date and time, the location goes in the Location field, and other details go into the reminder's notes as plain text. The original file is not changed or deleted.
- Past events are imported as completed and never ring.
Calendar export
With the unlock, Calendar export creates a standard .ics file on your device. It goes only where you save or share it through Android's save or share screen. The .ics file is not encrypted.
PDF export
When you export a PDF, Core Notes reads any text it finds in your photos and drawings, on the device, and prints it as a caption under each picture. The text-recognition engine is built into the app, and nothing is uploaded.
Reminder sounds
Reminders can use the default sound, a system sound, or an audio file you pick. A file you pick stays where it is; Core Notes only keeps permission to play it. If it is moved or deleted, the default sound plays.
What leaves your device
Only what you send yourself. Backups and exports, including .ics calendar exports, are saved where you choose with Android's file picker. Sharing opens Android's share screen, and the receiving app's own policy then applies. Tapping a link opens your browser. Sharing a crash log (Crash report on the lock screen, Share crash log after a crash, or Settings › About › Crash log) opens Android's share screen with the log attached and our support address filled in, and nothing is sent unless you finish sending it.
Importing from other note apps
Core Notes checks whether Google Keep, Samsung Notes, Evernote, Simplenote, Standard Notes, or Joplin is installed, only so it can show import steps for those apps. It does not read their data. It imports only files you export and choose, or notes you share to it.
Third parties
None are contacted by Core Notes. Google Play Billing handles the optional unlock.
Permissions
- Microphone and foreground service: only while you record an audio note, asked the first time you tap record.
- Calendar (read only): optional, asked only when you import from your device's calendars. Core Notes never edits them.
- Notifications: asked the first time you set a reminder.
- Alarms & reminders (exact alarms): optional. Exact times are on by default, but Android honors them only after you allow Alarms & reminders for Core Notes. Without it, alarms, the timer, and reminders may ring up to about 10 minutes late.
- Full-screen alerts (optional, in Settings): used only so alarms, the timer, reminders, and calendar events can fill the screen when they ring, even when your device is locked. If full-screen access is off, they show as a regular notification.
- Display over other apps (SYSTEM_ALERT_WINDOW): optional and off by default. Core Notes asks for it only when you turn on Show alarms over other apps in Settings, which opens Android's own Display over other apps page. It's used only to open the alarm screen over other apps while your device is in use, and it reads no data.
- Battery optimization exemption: asked only so alarms and reminders fire on time. Notes works without it.
- Do Not Disturb access: asked only while Ring on silent for reminders is on (it is on by default, and you can turn it off in Settings so reminders follow silent mode). With access, reminders can ring during Do Not Disturb.
- Foreground service: keeps an alarm or the timer ringing until you stop or snooze it, and a due reminder ringing until you tap Done or Snooze, or swipe it away.
- Run at startup, wake lock, and vibration: to restore reminders and alarms after a restart or time change, and to ring and vibrate on time.
- Biometric: optional fingerprint unlock. Android checks the fingerprint on the device; the app only receives a yes or no.
- Photos: added with Android's Photo Picker, which needs no storage permission. Core Notes sees only the photos you pick, and re-saves them without location or other EXIF data.
- Google Play billing: for the optional unlock.
- Not requested: internet, location, contacts, camera, storage, or writing to your calendars.
Purchases
Core Notes is free. Encrypted notes, encrypted backups, the Quick Bar and Quick Box widgets, simple in-note reminders, and the Clock (alarms, timer, stopwatch, and world clock) are free. An optional $4.99 one-time unlock through Google Play Billing adds the calendar, repeating and advanced reminders, calendar and .ics import and export, and the Today and Month widgets. No subscription. The unlock is remembered on this device and works offline, and it never locks you out of notes you already have.
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20. Core Scan
Core Scan is a document scanner for Android from Core Products & Services, LLC. It turns photos of pages into PDFs or JPGs on your device. No account is required.
No internet
Core Scan does not request Android's internet permission, so the app cannot connect to the internet. Your scans are not uploaded anywhere by Core Scan. Finding edges, cropping, filters, and text recognition all happen on your device. The first time you open Core Scan, and again after a reinstall, Android's Google Play Store app checks your Google Play purchase, so that start needs a connection. After that, Core Scan works offline. Core Scan has no crash-reporting SDK.
What stays on your device
- Your saved scans. PDFs and JPGs are saved to Documents › Core Scanned Documents, where other apps on this device can open them. They are not encrypted, and they stay after you uninstall Core Scan unless you delete them.
- Your settings, such as flash, auto edges, file size, name template, date format, icon, and text recognition languages.
- If you reinstall Core Scan and choose the Core Scanned Documents folder so it can list your older scans, Android remembers that folder access for Core Scan. Core Scan only accepts that one folder.
- An unfinished scan, so you can pick up where you left off if the app closes or crashes. Its pages are deleted when you discard them, retake or delete a page, or save the scan. Working files made while saving sit in the app's private cache and are deleted after the save.
- A crash log of the last 5 crashes: the error trace, the app version, the device maker and model, the Android version, and the time. File paths, URIs, file names, and coordinates are removed. It never includes page images or document text.
- The result of your Google Play purchase check, kept scrambled so it only works on this device.
- Everything above except your saved scans is kept in the app's private storage. Android backup is turned off for Core Scan, so this data is not copied to your Google backup or moved to a new device.
- Where you were: the tab and the step you were on (camera, review, or crop, with the page number), as a short note that Android keeps on your device so Core Scan can open where you left off (see section 4). It holds no pictures, pages, or file names.
Text recognition (optional, off by default)
Text recognition adds a hidden text layer so a saved PDF can be searched and its text selected. It is off until you turn it on. It runs entirely on your device using Tesseract, an open-source text recognition engine built into the app. All language files come with the app, so nothing is downloaded. When text recognition is on, Core Scan copies the files for the languages you choose into its private storage, and removes them when you turn a language or text recognition off. Those files hold none of your data. Core Scan does not keep a separate copy of the recognized text. It exists only inside the PDF you save.
What leaves your device
Only what you send yourself, plus one check: the first time you open Core Scan, and again after a reinstall, Android's Google Play Store app confirms your purchase with Google Play. Core Scan sends nothing itself, and Google's privacy policy applies to that check. When you share a scan, Android's share menu sends that file to the app you pick, and that app's own privacy policy then applies. Saved scans do not carry the location or camera details stored in an imported photo.
- Send to Core Sign: opens the saved PDF directly in Core Sign on the same device, with read-only access, through Android. Nothing is uploaded. If Core Sign is not installed, Core Scan opens its Google Play page instead.
- Opening a scan: a saved PDF opens in Core Sign when it is installed. If it isn't, you can get Core Sign on Google Play or open the PDF with another app on your device, and that app's own privacy policy then applies. A saved JPG opens in another app on your device, where that app's policy applies too. Nothing is uploaded.
- Sharing the crash log (optional): after a crash, Core Scan asks once whether you want to share the crash log by email with gotocorepstx@gmail.com. You can also share it from Settings › About › Crash log. Nothing is sent automatically, and nothing is sent unless you choose to send it.
Third parties
Core Scan contacts no third parties itself. Android's Google Play Store app checks your purchase with Google Play. No third‑party ads. No analytics. No tracking.
Permissions
- Camera: asked the first time you scan, and used only to take pictures of your pages while the scan screen is open.
- Google Play license check: so Android's Google Play Store app can confirm your purchase.
- Photos you import: chosen with Android's photo picker, which needs no storage permission. Core Scan sees only the photos you pick.
- Folder access after a reinstall (optional): chosen by you with Android's folder picker.
- Not requested: internet, storage, location, microphone, or contacts.
Purchases
Core Scan is a $4.99 one-time purchase on Google Play. No trial. No subscriptions. No in-app purchases.
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21. Core Sign
Core Sign is a PDF reader with fill and sign tools for Android. Reading, saving, sharing, exporting, printing, and splitting PDFs are free. No account is required. Its vault is encrypted. The rest of the app is not.
No internet
Core Sign does not request Android's internet permission, so the app cannot connect to the internet. Your documents and signatures are not uploaded anywhere by Core Sign. All processing happens on the device.
What stays on your device
- Your settings, your saved signature and initials, the documents you work on, and your folders (their names, colors, and order), kept in the app's private storage. Folders exist only in Core Sign; making, renaming, or moving between them doesn't change any file or folder on your device.
- Copy or Link: each PDF you import is a Copy or a Link. For a Copy, Core Sign keeps its own copy, and your original is never changed. For a Link, Core Sign keeps a working copy for your edits and the file's address, and Android's file permission lets it reopen the original where it is. Photos, and files opened from another app, are always copies.
- Your original files: Core Sign changes a linked original only if you choose Overwrite original, and deletes it only if you choose Delete from device (for a linked folder, that deletes the folder and everything in it). Each asks you to confirm first. Before overwriting, Core Sign keeps a backup of the original in its private storage and deletes it once the new version checks out; if the original can't be put back, the backup stays there.
- Trash: documents you delete stay in Trash for 30 days, then are removed. A Link you remove from Core Sign is dropped right away, and Core Sign gives back its access to the original.
- A crash log of the last 5 crashes, kept in the app's private storage: the error trace, the app version, the device model, and the Android version, with a text-layer report for the last page you opened (line positions and font names, never document text). Nothing is sent unless you share a log.
- Where you were: the screen and tab, the folder, and, for a document that is not in the Vault, which document it is, its page, and whether Reader mode was on, as a short note that Android keeps on your device so Core Sign can open where you left off (see section 4). A Vault document is never in it.
- Android backup is turned off for Core Sign.
Vault
Your signatures, initials, and the documents you store in the Vault are encrypted with AES-256-GCM. The key stays in the Android keystore and is wrapped by a PIN or pattern you set, or a strong biometric if you turn it on. Your PIN or pattern always works too. Storing a document in the vault stores a copy; your original file is not deleted. When you open a vault document, the decrypted working copy is removed when you close it or leave the app, and any copy left by a crash is cleared the next time the app starts. Documents you are working on outside the vault, and files you export, are not encrypted. Your PIN or pattern cannot be recovered. Repeated wrong attempts add a growing wait, up to 15 minutes. After you leave Core Sign, the Vault stays open only for the time you choose in Settings (Immediately, or 1, 5, 10, 15, or 60 minutes; the default is 10 minutes), and it is always locked when the app starts fresh (see section 4).
What leaves your device
Only what you send yourself. When you share, export, or print, Android sends the file to the app or printer you pick, and that app's own policy then applies. If you link a file that a cloud storage app provides, Core Sign reads it, and writes or deletes it only when you choose to, through that app, which may sync the change under its own policy. Sharing a crash log opens Android's share menu with our email address filled in, and nothing is sent unless you finish sending it.
Third parties
None are contacted by Core Sign. Google Play Billing handles the optional unlock.
Permissions
No permissions to grant. Core Sign opens the PDFs, folders, and images you choose through Android's file picker. For a Link, Android lets Core Sign keep access to that file or folder until you remove it from Core Sign. The install-time permissions are Google Play billing, used for the unlock, and biometric, used only if you turn on biometric unlock for the vault.
Purchases
Core Sign is free to read, save, share, export, print, and split, and folders are free. A $9.99 one-time unlock through Google Play Billing adds filling, signing, markup, form filling, redaction, page tools (rotate, duplicate, delete, extract, reorder, insert), the vault, and merging. No trial. No subscription. The unlock stays associated with the Google Account that bought it.
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22. Core Utilities
Core Utilities is a set of everyday tools that use the device's own sensors and math. No account is required. After the first launch, every tool works offline except the network tools (Speed Test, Wi-Fi File Share, and the FTP client), which are off until you turn on Network tools in Settings. The first launch needs a connection so Android's Google Play Store app can confirm your purchase.
Speed Test log: if a Speed Test fails, Core Utilities saves the step that failed and the error details in its private storage on your device to help explain the failure, not in Download or shared folders. It is never uploaded by Core. Core Utilities does not keep your Speed Test results. M-Lab keeps a copy of every test, as described under Network tools.
What stays on your device
- Your settings and calibration values, in the app's private storage. They are removed when you uninstall.
- Saved FTP connections (server, user name, and password), stored encrypted on your device.
- The one folder you choose to share with Wi-Fi File Share. Files are shared in place and never copied to Core.
- A crash log of the last 5 crashes, kept in the app's private storage: the app version, the device model, the Android version, and the error. It is never sent automatically; you choose whether to share it from Settings › About › Crash log.
- Where you were: which page or tool is open, as a short note that Android keeps on your device so Core Utilities can open where you left off (see section 4). It holds nothing you typed, measured, or picked.
- Android backup is turned off for Core Utilities.
Pictures and videos
The Image & Video tools (Vectorize, Compress & Resize, Strip Metadata, Trim Video, Video to GIF/WebP, and Color Picker) and QR Code open only the files you choose, through Core Gallery or Android's picker, and process them on this device. Nothing is uploaded. The original file is not changed. Each result is saved as a new file in folders other apps on this device can see: pictures and GIFs in Pictures/Core Utilities Images, videos in Movies/Core Utilities Videos, and SVG drawings in Documents/Core Utilities Vectors (on Android 8 and 9, the system Save screen opens instead). Core Utilities does not ask for permission to read your photos.
Microphone
Used only while Sound Meter is open, to measure loudness. Nothing is recorded, saved, or sent.
Network tools (off by default)
Turn them on in Settings › Network tools.
- Speed Test: connects to Measurement Lab (M-Lab) using its open NDT7 test, only when you tap Start test, never in the background. A test runs for a few seconds in each direction, and the data it uses depends on your connection speed and counts toward a mobile data plan. M-Lab publishes every test result as public open data, including your IP address, the date and time, and the measured speeds. Core sends no identifier, name or account to M-Lab. If you don't want your IP address published, don't run Speed Test. M-Lab's privacy policy (https://www.measurementlab.net/privacy/) applies to that connection. M-Lab's policy doesn't allow people under 16 to use its speed test, so Core Utilities is meant for ages 16 and up.
- Wi-Fi File Share: serves files only to devices on your Wi-Fi, never through Core or the internet. While sharing is on, the app shows your device's local IP address, port, user name, and a one-time password, and anyone on the same Wi-Fi who has that password can open the folder you chose to share. SFTP is the default and is encrypted. Plain FTP is available only if you turn it on, and it is not encrypted: file names, files, and the password travel in readable form on your Wi-Fi. Sharing stops when you tap Stop, after 15 minutes without use, or when Wi-Fi drops. Use trusted networks.
- FTP client: connects only to servers you add, using SFTP (encrypted) by default. Plain FTP is available only if you choose it, and it is not encrypted. Core never sees your servers, files, or passwords.
Third parties
Measurement Lab (M-Lab), only when you run Speed Test. The FTP client connects only to servers you choose yourself. Android's Google Play Store app confirms your purchase with Google Play when you first open the app, and again after the confirmation expires. Core Utilities contacts no other third parties.
Permissions
- Internet and network state: used only for Speed Test, Wi-Fi File Share, and the FTP client, and only after you turn on Network tools.
- Microphone (optional feature): only for Sound Meter.
- Notifications and foreground service: to show and keep Wi-Fi File Share running while it is on, with a Stop control.
- Vibration: for optional haptic feedback.
- Google Play license check: so Android's Google Play Store app can confirm your purchase.
- Folder access: Wi-Fi File Share and the FTP client use only the single folder you pick through Android's folder picker. Core Utilities does not request All files access and cannot share your whole storage.
- Storage (older Android versions only): to read the files you share or transfer on Android 12 and older, and to write them on Android 10 and older.
- Motion, compass, light and barometer sensors need no permission. On Android 12 and newer, Core Utilities asks for the high sampling rate sensors permission (android.permission.HIGH_SAMPLING_RATE_SENSORS) so the Level and other motion tools read the sensors quickly. This data stays on your device. Tools that need a sensor your device lacks show "Not on this device".
- Not requested: location, camera, contacts.
Purchases
Core Utilities is a $2.99 one-time purchase on Google Play. No trial. No subscription. No in-app purchases. The first time you open Core Utilities, it checks your Google Play purchase, and you can't use it until the check succeeds. After that, every tool works offline except the network tools.
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23. Core Weather
Core Weather is provided free of charge. It shows Dual °F/°C for a place entered by the user, or for the device location only if Detect is chosen. Detect is one-shot and opt-in. It is not continuous tracking, and it is not saved as a profile. Core Weather requires a connection for the forecast, place search, and alerts.
What stays on your device
- Your settings (temperature units, sound, vibration, alert options, theme).
- Your saved place (the text you typed, or the place that Detect location found).
- The last forecast, with the rounded coordinates for your saved place and a list of alerts already shown, so widgets and notifications don't repeat themselves.
- A crash log of the last 5 crashes, kept in the app's private storage: the error trace, the app version, the device model, and the Android version. It does not include your place or location. It is never sent automatically; sharing it opens Android's share menu with our email address filled in, and nothing is sent unless you finish sending it.
- This data is kept in the app's private storage. Android backup is turned off for Core Weather, so this data is not copied to your Google backup.
What leaves your device
Core Weather needs the internet. All requests use HTTPS. Every request goes straight from your device to the service, so that service sees your IP address. Requests also carry a User-Agent label that names Core Weather.
- Place lookup (when you type a place): the city or postal code you type is sent as you typed it. We cannot round a typed place name. Services used: Nominatim (OpenStreetMap), Zippopotam.us (5-digit U.S. ZIP codes), and the U.S. Census Geocoder (backup for ZIP codes only). Place search runs only when you search; it is never repeated in the background. By default, place search uses the public OpenStreetMap Nominatim server. In Settings you can enter a different place-search server; if you do, the place you type, or the rounded Detect point, goes to that server instead, under its own terms.
- Detect location (optional): the app asks Android for your location one time, only when you tap Detect location. Before any network request, it rounds the coordinates to 1 decimal place (0.1°, roughly 11 km or 7 miles). The rounded point goes to Nominatim (OpenStreetMap) to find the place name. If no name is found, the place is saved as "Home" with the rounded coordinates. Then Detect location turns itself off. The app keeps the place it found, not a live location.
- Forecasts: rounded coordinates go to MET Norway (the Norwegian Meteorological Institute, api.met.no). MET Norway logs the IP address and the requested coordinates on its servers in Oslo, Norway.
- U.S. observations and severe alerts: for U.S. places, rounded coordinates also go to the U.S. National Weather Service (api.weather.gov). Outside the U.S., NWS is not contacted.
- Background refresh: while you have a saved place, Core Weather refreshes about every hour by default. You can change this to every 30 minutes, 1 hour, or 3 hours in Settings. Refreshes run only when you have a network connection. For U.S. places with alerts turned on, a separate alerts-only check runs about every 15 minutes; it does not run when alerts are off. Outside the U.S., background refresh runs only while a Core Weather widget is on your home screen; otherwise the forecast updates when you open the app. Opening the app fetches new data only if the last forecast is more than 10 minutes old. Each refresh sends the saved rounded coordinates to the forecast and alert services above, never your typed place name, and it never repeats a place search. Background refresh never turns on GPS. Widgets redraw from the saved forecast without a network request.
- Links you tap: "More on this warning" and similar links open forecast.weather.gov or Windy.com in your browser, with rounded coordinates or your ZIP code in the address. That website's own policy applies.
Third parties
MET Norway, Nominatim / OpenStreetMap, Zippopotam.us, U.S. Census Geocoder, U.S. National Weather Service, plus forecast.weather.gov or Windy.com only when you tap a link. Core has no control over their logs.
Permissions
- Internet and network state: to get forecasts and place data, and to refresh only when a connection is available.
- Location (approximate and precise): optional. Used only when you tap Detect location. Typing a city or ZIP works without it.
- Notifications and vibration: for weather updates and severe-weather warnings. You can turn these off in the app or in Android settings.
- Run at startup, wake lock, and a short background task: to keep the scheduled refresh running after a restart.
Purchases
None. Core Weather is free and has no in-app purchases.
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24. Core Workout
Core Workout is a paid exercise interval timer for Android. It runs timers on the device for formats such as EMOM, AMRAP, Interval, Tabata, For Time, HIIT, Custom, Saved workouts, and chained workouts. No account is required. Voice cues and workouts stay on the device. Timing a workout does not require a network connection.
Network
Core Workout does not request Android's internet permission, so the app cannot connect to the internet. Android's Google Play Store app handles the one-time unlock and its license checks. Workouts, cues, and timers are not uploaded. Day-to-day timing does not need a network connection. Core Workout has no crash-reporting SDK.
What stays on your device
- Your settings (volume, voice, vibration, keep-screen-on, and related options).
- Saved workouts, presets you hide or copy, unfinished custom starts kept for later save, and chained workouts.
- Built-in voice cue files that ship inside the app.
- A local record of whether the one-time unlock is active.
- A crash log of the last 5 crashes, kept in the app's private storage: the error trace, the app version, the device model, and the Android version. It stays on the device until you choose to share one.
- This data is kept in the app's private storage. Android backup is turned on for Core Workout. Android Auto Backup can include settings, saved workouts, and your trial start date. Google runs that backup, not Core. You can turn it off in Android's backup settings.
Core Workout saves the date your 14-day trial started in the app's private storage on this device. Android backup and Google Play services Block Store keep a copy for you. Block Store copies it to your Google backup only when Google can end-to-end encrypt it. That way, clearing data or reinstalling usually doesn't restart the trial. Google runs these, not Core; Core never receives the date.
Backup and restore
Optional Backup and Restore use Android's system save and open sheets. Backup writes a CoreWorkout-backup.json file you choose a location for. Restore reads a file you pick and merges saved workouts by id. Core does not upload that file. A file that is not a Core Workout backup changes nothing.
What leaves your device
Only purchase and license checks, handled by Android's Google Play Store app. Android backup and Google Play services Block Store can keep a copy of your trial start date, as described above. A backup file you save can leave the device only if you copy or share it yourself. A crash log leaves the device only if you share it through Android's share menu.
Third parties
Google Play Billing handles the one-time purchase and related license checks. Google Play services Block Store keeps a copy of the trial start date. Core Workout contacts no other third parties.
Permissions
- Internet: not requested. Android's Google Play Store app handles the unlock and its license checks.
- Notifications and foreground service: so the timer can keep running with the screen off and show pause, resume, skip, and stop controls.
- Vibration: optional cues you can turn off.
- Wake lock: to keep the timer deadline accurate while the screen is off.
- Battery optimization exemption (asked, optional): so the system is less likely to stop a running timer. You decide in the system dialog.
- Google Play billing: for the unlock.
Purchases
Core Workout offers a 14-day free trial, then a one-time $4.99 unlock through Google Play Billing. There is no subscription. The unlock stays associated with the Google Account that bought it.
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25. Trio Live Wallpapers
Trio Live Wallpapers is a live wallpaper app for Android from Core Products & Services, LLC. It sets your GIFs, videos, and photo slideshows as live wallpapers. No account is required.
No internet
Trio Live Wallpapers does not request Android's internet permission, so the app cannot connect to the internet. Trio itself never sends anything from your device. The purchase check is made by Android's Google Play Store app. The first time you open Trio, it checks your Google Play purchase; the wallpaper stays blank until then. After that, it works offline. Tapping the Privacy link opens your browser.
What stays on your device
- Your wallpaper settings and choices, in the app's private storage.
- Videos are converted on this device to a new looping GIF, using your device's own video decoder and processor. The original video is never changed.
- The file you pick is copied; your original is never changed. Saved wallpapers go to
Pictures/Trio Live Wallpapers, where your gallery app can see them. Copies in Pictures stay after you uninstall Trio unless you delete them. - Hidden Mode keeps saved wallpapers in Trio's private storage instead: they don't show in other apps, and they're deleted if you uninstall Trio.
- Slideshow folders you pick are read in place and never copied.
- Deleting a wallpaper in Trio deletes the file, including files in a folder you picked, after you confirm.
- A crash log of the last 5 crashes, kept in the app's private storage: the error trace, the app version, the device model, and the Android version. It never includes file names, paths, pictures, or location.
- Android backup is turned off for Trio Live Wallpapers.
What leaves your device
Only what you send yourself, plus one check: the first time you open Trio, Android's Google Play Store app confirms your purchase with Google Play. Trio sends nothing itself. The crash log is never sent automatically. Settings › About › Crash log opens Android's share menu with our email address filled in, and nothing is sent unless you finish sending it.
Third parties
Trio Live Wallpapers contacts no third parties itself. Android's Google Play Store app checks the purchase with Google Play. No third‑party ads. No analytics. No tracking.
Permissions
- Set wallpaper: to set your live wallpaper.
- Google Play license check: so Android's Google Play Store app can confirm your purchase.
- Photos, videos, and folders: chosen with Android's photo picker and folder picker, which need no storage permission. Trio sees only what you pick.
- Not requested: internet, location, camera, microphone, or contacts.
Purchases
Trio Live Wallpapers is a $4.99 one-time purchase on Google Play. No trial. No subscriptions. No in-app purchases.