Sudoku Legends · Revo Games
Privacy Policy
Last updated: 10.10.2026
1. Who we are
Sudoku Legends is published under the Revo Games brand by Revortex OÜ, a private limited company registered in Estonia. Revortex OÜ is the controller of the personal data described in this policy.
- Registry code: 17192374 (Estonian Business Register)
- Address: Järvevana tee 9, 11314 Tallinn, Estonia
- E-mail: support@revo.gs
2. Scope
This policy covers the Sudoku Legends app for iOS and Android (the “App”, shown as “Sudoku” on your home screen) and the pages of revo.gs that describe it. It does not cover the App Store or Google Play, which Apple and Google run under their own privacy policies.
3. Your account
The App does not ask for your name, e-mail address, phone number or a password. The first time it reaches our server, it creates an anonymous account for this installation: a random account ID that is not derived from your device or your identity. Your progress is stored under that ID.
- The account belongs to this installation. There is no sign-in, so it cannot be moved to another device, and it cannot be recovered once the App is deleted or its data is cleared.
- The App gives the account a default username, which you can change in your profile. Usernames are not shown to other players.
4. Data we process
a) Account and game data, stored on our server
- Account: the account ID, when it was created, and your username.
- Sign-in sessions: the IP address and device user agent our authentication server records for a session, and its timestamps.
- Progress: experience points (XP), level, Daily Challenge streaks, and your in-app settings (timer, haptic feedback, language).
- Finished games: mode (quick game or Daily Challenge), difficulty, start and end time, playing time, result, score, mistakes, hints and undos, whether notes were used and, for Daily Challenges, the sequence of moves, which our server replays to verify the result.
b) Analytics and crash reports, only if you allow them
See section 6.
c) Feature configuration
The App uses Firebase Remote Config to receive settings that switch features on or off. For this it sends Google an installation identifier generated by Firebase (not your account ID) and basic app and device information, such as the app version, platform, language and region. This happens whether or not analytics is on, because the App needs it to work as configured.
d) Data kept only on your device
An unfinished game, results waiting to be uploaded, your settings and your analytics choice are stored on your device so the App works offline. They are removed when you delete your account, delete the App or clear its data.
e) When you contact us
Your e-mail address and what you write to us.
We do not collect your precise location, contacts, photos, payment information or advertising identifier (IDFA on iOS, AAID on Android). The App shows no advertisements.
5. Why we use data, and our legal bases
- Providing the game: keeping your account, progress, XP, streaks and settings, and running and verifying Daily Challenges. Legal basis: performance of our contract with you (Art. 6(1)(b) GDPR).
- Analytics and crash reports: understanding how the App is used and fixing crashes. Legal basis: your consent (Art. 6(1)(a) GDPR), which you can withdraw at any time.
- Feature configuration, security and abuse prevention: Remote Config, sign-in session records, and detecting manipulated Daily Challenge results. Legal basis: our legitimate interest in running a secure, working service (Art. 6(1)(f) GDPR).
- Support: answering your messages. Legal basis: performance of our contract, or our legitimate interest in helping you.
- Legal obligations: keeping records the law requires (Art. 6(1)(c) GDPR).
We do not sell personal data, use it for advertising, or track you across other companies’ apps or websites.
6. Analytics and crash reports: your choice
On first launch the App asks whether you want to share usage data. If you agree, it uses Google Analytics for Firebase and Firebase Crashlytics, provided by Google:
- Analytics: events about how you use the App and play (for example a game started, completed or abandoned, hints and mistakes, Daily Challenges, XP and level changes), sent with your account ID as the user ID, a Firebase app-instance ID, the device model, operating system, app version, language, time zone, and a coarse location (country or region) that Google derives from your IP address.
- Crash reports: technical details of a crash or error (stack trace, device and app state), sent with your account ID.
If you decline, both stay off. Collection is off on a new installation until you agree. You can change your choice at any time in Settings › Privacy › Share usage data; when you turn it off, collection stops and crash reports that have not been sent are deleted from the device.
Analytics data is exported daily to Google BigQuery, stored in the EU, where we analyse it in aggregate.
7. Service providers and other recipients
We share personal data only with service providers that process it on our behalf:
- Google (Google Ireland Limited and Google LLC): Firebase Analytics, Crashlytics and Remote Config, and BigQuery storage for analytics data.
- Hetzner Online GmbH: hosting of our game server, where your account and game data are stored.
- Cloudflare, Inc.: hosting and delivery of revo.gs, and the connection between the App and our game server.
- Microsoft: our e-mail service, for messages you send us.
We may also disclose data where the law requires it, or to establish or defend legal claims. Apple and Google process data about your download through their stores under their own privacy policies.
8. Transfers outside the EEA
Google, Cloudflare and Microsoft may process data in the European Union, the United States and other countries; where that involves a transfer outside the European Economic Area (EEA), they rely on the EU–US Data Privacy Framework or on the European Commission’s Standard Contractual Clauses.
9. How long we keep data
- Account, progress and finished games: until you delete your account. We do not delete inactive accounts automatically today; if we start to, we will say so here first.
- Sign-in session records (IP address, user agent): while the session exists, and never longer than the account.
- Analytics data: user-level data in Google Analytics for 14 months; in our BigQuery export until we delete it, or until your account deletion is processed (section 10).
- Crash reports: about 90 days in Crashlytics.
- Server logs: technical logs that can contain IP addresses are kept only as long as needed for security and troubleshooting.
- Backups: encrypted backups of the game server are kept for up to 30 days; data you delete disappears from them when they expire.
- Support e-mails: as long as needed to handle your request and any follow-up.
- Deletion records: see section 10.
10. Deleting your account and data
In the App: open Settings › Account & Help › Delete account. After you confirm, the App asks our server to delete your account, username, progress, finished games and sign-in sessions, which the server does at once and permanently. When the server confirms, the App clears your game data, settings and sign-in on this device (keeping only the display theme), turns analytics off, resets its analytics identifier and starts again with a new, empty anonymous account. If the connection is lost before the server answers, the App tells you so and keeps the deletion pending: each time it opens with a connection it asks our server again, and it clears this device once the server confirms the deletion. Until then the Delete account screen keeps showing your Account ID, which you can send to support to have the deletion finished; the App on this device is not told when support finishes it, so remove the App or clear its data afterwards. Installation identifiers that Google’s SDKs keep for feature settings and crash reporting stay on the device until you remove the App. Deletion cannot be undone.
Without the App: follow the steps at revo.gs/games/sudoku-legends/delete-account. Because the account is anonymous, we need the Account ID shown on the App’s Delete account screen to find it, and we check every request before deleting anything.
Analytics and crash data linked to your account ID are not deleted from the device side. We keep a deletion record (the account ID, the date and how the request was made) and use it to delete that data from Google Analytics and our BigQuery export within 30 days; crash reports expire on their own after about 90 days. We delete the deletion record within 12 months. For deletions requested in the App we also keep a receipt that contains no account ID — a one-way fingerprint of the request and its date — so the App can still confirm the deletion later.
11. Your rights
Under the GDPR and similar laws you can ask us for access to your data and a copy of it (portability), for correction, for deletion and for restriction of processing, and you can object to processing based on our legitimate interests. You can withdraw your consent to analytics at any time in Settings; this does not affect processing that happened before. To exercise a right, write to support@revo.gs and include your Account ID. We answer within one month.
You can also complain to a data protection authority, for example the Estonian Data Protection Inspectorate (Andmekaitse Inspektsioon, www.aki.ee), or the authority where you live.
12. Children
The App is not directed at children under 13, and we do not knowingly collect personal data from them. If you believe a child under 13 has used the App, contact us and we will delete the account.
13. Security
Connections between the App and our server are encrypted (HTTPS). Database access rules let an account read and change only its own data, and Daily Challenge results are verified on the server. No system is completely secure; if a breach affects your data, we will notify you and the authorities as the law requires.
14. Changes to this policy
We update this policy when the App or our practices change, and change the “Last updated” date above. For significant changes we will also inform you in the App or on our website.
15. Contact
Revortex OÜ, Järvevana tee 9, 11314 Tallinn, Estonia. E-mail: support@revo.gs. Help with the game: revo.gs/games/sudoku-legends/support.