Privacy Policy
Mivrise (“we”) operates the Miv Sudoku app (the “app”) and mivrise.com (the “site”) and processes only the minimum information needed. The app has no accounts, and most records stay on your device.
1. At a glance
- No sign-up or login. We do not ask for your name, phone number or address.
- Puzzle records and settings are stored only on your device.
- Your nickname and result appear in public rankings only if you choose to publish them (planned feature).
- Ads are requested only when you choose to watch one, and we request non-personalized ads.
- Google Play handles payments; the app never receives your card details.
2. Information stored only on your device
To let you resume puzzles and review your progress, the app stores the following on your device. It is not sent to our servers.
- Puzzle entries, notes and progress; completion dates, solving times, mistakes and hints
- Statistics by level, calendar checkmarks, streaks and monthly trophies (calculated on the device)
- Whether the guide was used and how many guided games you finished; settings (large text, theme, input style, etc.); daily free-play count
- A nickname written on a personal record (not visible to anyone unless you publish it)
Uninstalling the app, or Android Settings → Apps → Miv Sudoku → Storage → Clear data, erases all of it.
3. Daily rankings (planned feature)
Only if you choose ranked play, our ranking server on Cloudflare Workers and D1 processes:
- A random per-installation identifier, puzzle date, start token, start time and attempt status
- The completed grid (to check the solution), elapsed time, hint count and whether the guide was used (to separate the standard and guided leagues)
- Your nickname if you publish your result (“Anonymous” if left blank)
- Your IP address, to limit repeated requests (processed, not stored with the record)
A published result shows your rank, nickname, time and hint count to others. Withdraw my result on the same device to remove the listing and erase the nickname on the server. The identifier and attempt record used for the first-attempt rule remain; to remove them too, request deletion.
Clearing device data alone leaves the server record in place and removes the key needed to withdraw. Please withdraw before uninstalling if you do not want a listing to remain.
4. Tomorrow's reminder
If you turn it on, Android checks notification permission and the app schedules one local reminder for 9 AM the next day, Korea time. No push token is sent to any server, and you can cancel it on the completion screen.
5. Ads (Google AdMob)
A rewarded ad is requested only when you choose to watch one for an extra game or a hint. No ads pop up during a puzzle.
The app checks Google's consent flow and then requests non-personalized ads. Google AdMob may process your IP address, device and advertising identifiers, ad interactions and diagnostics to deliver and measure ads and prevent fraud. See Google's ads SDK data disclosure and the Google Privacy Policy.
You can reset or delete your advertising ID in Android Settings → Privacy → Ads.
6. Purchases (Google Play · RevenueCat)
Google Play processes payment for the one-time purchase. The app never receives card numbers or other payment details.
To verify and restore purchases, RevenueCat processes a random app user identifier, purchase history and entitlements. RevenueCat Privacy Policy
7. Service providers and international transfers
The providers below process information only when you use the related feature. Their servers are outside Korea (mainly in the United States), and data is transferred over the internet when you use that feature.
| Provider (country) | Information | Purpose | Retention |
|---|---|---|---|
| Google LLC (US) | IP address, advertising ID, ad interactions | Rewarded ads | Per Google's policy |
| Google LLC (US) | Purchase history | Payment (Google Play) | Per Google's policy |
| RevenueCat, Inc. (US) | App user ID, purchase history | Verify and restore purchases | Until deletion is requested |
| Cloudflare, Inc. (US) | Site access logs, ranking records | Hosting, ranking server | Ranking records: 1 year from the puzzle date |
If you do not want your data transferred abroad, simply do not use those features (watching ads, purchasing, ranked play). Solving puzzles and keeping records on your device work without them.
8. Visiting mivrise.com
The site has no ads, analytics or cookies. Our host (Cloudflare) may process connection details such as your IP address and the requested path to deliver and secure pages.
If you pick a language, that choice is remembered only in your browser's storage (localStorage). It is not sent to us.
9. Retention and deletion
- Information on your device: until you uninstall the app or clear its data
- Ranking records: deleted 1 year after the puzzle date, or within 10 days of a deletion request
- Support emails: deleted 1 year after we reply (or until any dispute is resolved)
Electronic files are deleted so that they cannot be recovered.
10. Your rights
You may ask to access, correct, delete or stop processing your information at any time. See data deletion or email contact@mivrise.com. We respond within 10 days of receiving your request.
The app is not directed at children under 14 and we do not knowingly collect their personal information. A parent or guardian may ask us to delete a child's public record.
11. Privacy contact
Privacy contact: Mivrise Customer Support · contact@mivrise.com
Users in Korea may also contact the Personal Information Dispute Mediation Committee (1833-6972) or the KISA Privacy Infringement Report Center (118).
12. Changes
We will post changes on this page 7 days before they take effect, or 30 days before for significant changes that work against you.
This is a draft prepared on 5 November 2026 and takes effect on the app's release date.