Privacy Policy
Math Rhombus · last updated
1. Summary
Math Rhombus (“the app”) is a number-puzzle game published by Cool App Helpdesk. It is played offline, by players of every age, including children.
- There is no account, no sign-in and no analytics.
- No ads before 1 September 2027. From then, a small banner from Google AdMob appears at the bottom of two menu screens — never during a puzzle. Those ads are child-safe and non-personalised (see section 5).
- Nicknames, stars, levels and settings are stored only on your device. They are never sent to us or anyone else.
- The only thing that can ever reach the developer is a feedback message or game idea that someone writes in Settings → Feedback and sends by tapping Send. That screen is behind a grown-up check, so a child cannot open it alone.
2. Data we collect
Playing the game sends nothing to us. We receive data only when someone opens Settings → Feedback (after answering the grown-up question), writes a message and taps Send. That message contains:
| Data | Why | Required? |
|---|---|---|
| Message type, subject and message text (for a game idea: its name, how it plays, a similar game and who it is for) | To read and act on the feedback | The message is required |
| Email address | Only to reply | Optional — left out if the field is empty |
| App version, device maker and model, Android version, app language, time sent | To reproduce and fix bugs | Sent with every message |
Feedback never includes player nicknames, stars, progress or any device identifier (no advertising ID, no Android ID).
3. Data stored on your device
| Item | Where | Sent off device? |
|---|---|---|
| Player nicknames and who is playing | Local app storage (DataStore) | Never |
| Stars, solved levels, hints left and the board in play, per player | Local app storage (DataStore) | Never |
| Settings: game style, language, check mode, vibration | Local app storage | Never |
| A feedback message being written | Memory only, until sent or closed | Only when you tap Send |
Puzzles are generated on the device from a fixed number for each level; nothing is downloaded. Android’s own device backup, if you have it turned on, may copy the app’s small settings file to your Google account under Google’s terms; game progress is not included.
4. Permissions used
| Permission | Reason | When asked |
|---|---|---|
INTERNET | To send a feedback message or game idea that you choose to send, and, from 1 September 2027, to load the advertising banner. The puzzles themselves never need the internet. | Auto-granted (normal permission) |
The app asks for no other permission: no location, camera, microphone, contacts, photos or files.
5. Network activity and third parties
The app contains no analytics SDKs, no crash-reporting SDKs and no social or attribution SDKs. It makes two kinds of network request:
- Feedback — a message you send, over HTTPS, to the developer’s own feedback service hosted on Google Cloud. Messages are used only to reply and improve the app, and are never sold or shared.
- Advertising (from 1 September 2027) — the app includes the Google Mobile Ads SDK (AdMob). Before that date it is never started and sends nothing. From that date it shows one banner at the bottom of the Home and world-map screens; there are no ads on the puzzle screen, no full-screen ads and no rewarded ads.
Because children play Math Rhombus, every ad request is marked as directed to children (COPPA) and as coming from a user under the age of consent (GDPR), and ads are limited to content rated G (general audiences). With these settings Google shows only non-personalised ads: no interest-based advertising and no remarketing. To show the ad, measure it and prevent fraud, Google receives technical information such as the IP address, the device model and Android version and the device’s advertising ID (which you can reset or delete in Android Settings → Privacy → Ads), under Google’s privacy policy and its rules for partner apps. The developer receives only aggregated earnings reports, never information about an individual player.
Settings → Privacy policy opens this page in your web browser, also after the grown-up question.
6. Children’s privacy
Math Rhombus is made for players of all ages, including children under 13. It is designed to comply with the U.S. Children’s Online Privacy Protection Act (COPPA), the EU/UK GDPR rules for children and Google Play’s Families policy:
- The game collects no personal information from anyone who plays it. Nicknames stay on the device and can be any word; we suggest not using a real full name.
- The feedback forms and the link to this page are behind a grown-up check (a multiplication question). They are meant for parents and adult players.
- Ads (from 1 September 2027) are child-directed, non-personalised and rated G, and appear only on menu screens. There are no in-app purchases, no chat and no way to contact other players.
If you believe a child has sent us a message with personal information, email us and we will delete it.
7. Data retention and deletion
Everything on the device stays until you delete it: delete a player in Players, use Settings → Reset progress, clear the app’s storage in Android Settings → Apps → Math Rhombus → Storage → Clear storage, or uninstall the app.
Feedback messages are kept only as long as needed to answer and act on them. To have a message you sent deleted, email the address below; no account is needed.
8. Security
App data is held in the app’s private storage, protected by Android’s built-in application sandboxing. Feedback is sent over encrypted HTTPS connections. The app is distributed through the Google Play Store, which verifies the developer signing key on every update.
9. Changes to this policy
If any material aspect of how the app handles data ever changes, this page will be updated and the “last updated” date above will be bumped. Continued use after a change constitutes acceptance.
10. Contact
Questions or feedback? Email coolapphelpdesk@gmail.com.