ChessImprover

Privacy Policy

Last updated: July 22, 2026

This Privacy Policy explains how ChessImprover ("we", "us") handles information. It covers the ChessImprover mobile apps for Android and iOS and the web app at chessimproverapp.com (together, "the app"). ChessImprover is an independent, free chess-training app. By using the app you agree to this policy.

1. Information stored only on your device

The following stay on your device and are not transmitted to us:

• Your opening repertoires, imported lines, and folders
• Games you play against the engine and their reviews
• Puzzle progress, ratings, and streaks
• App settings (themes, sound, notification preferences)

Uninstalling the app removes this data from your device.

2. Crash and performance data

We use Firebase Crashlytics (a Google service) to receive automatic reports when the app crashes or becomes unresponsive. These reports help us fix problems and may include:

• The type of crash and a stack trace (including native engine crash diagnostics)
• Device model, operating-system version, and app version
• Device state at the time of the crash (e.g. memory/storage status) and a random installation identifier

Crash reports do not contain your name or contact details.

3. Usage and analytics data

We use Firebase Analytics (a Google service) to understand how the app is used in aggregate so we can improve it. This may include:

• A random app-instance identifier
• Device and operating-system information
• In-app events, such as which screens you open and which features you use — for example that a game against the computer ended, the strength of the bot, and whether it was a win, loss or draw; that a puzzle was solved or missed; or that an opening repertoire was imported
• Coarse, banded summaries of your progress — for example a rating band such as "800-999" rather than an exact rating
• An approximate, coarse location derived from your IP address (e.g. country/region)

Analytics events never include your games, positions, moves, or any free text — only the anonymous facts listed above.

We do not collect the device advertising ID, and the app contains no advertising. We do not track you across other apps or websites.

You can turn this off at any time: Settings → Privacy → "Share anonymous usage data". Switching it off stops collection at the source — nothing further is recorded or sent. Crash reports (section 2) are separate and continue.

4. Network requests to Lichess

When you explore openings on the analysis board and a position is not already covered by the app's bundled opening data, the app may request opening statistics from the public Lichess Opening Explorer API. This sends only the chess position being viewed (in standard FEN notation) — no personal information. This does not happen during normal play or for common openings. Lichess's handling of such requests is governed by its own privacy policy.

5. What we do not collect

• No account, name, email address, or password (the app has no sign-in)
• No contacts, photos, microphone, or precise GPS location
• No advertising identifiers, and no third-party advertising
• We do not sell or rent personal information to anyone

6. How we use the data

Crash and analytics data are used solely to diagnose problems, improve stability, and guide which features to develop. We do not use it to identify you personally or to target advertising.

7. Service providers

We use Google Firebase (Crashlytics and Analytics) as a data processor. Data collected through these services is processed by Google in accordance with the Firebase Privacy and Security terms and the Google Privacy Policy, and may be processed on servers located in the United States or other countries.

8. Data retention

Crash reports and analytics data are retained according to Firebase's standard retention periods (for example, Crashlytics retains crash data for approximately 90 days). On-device data persists until you delete it or uninstall the app.

9. Children's privacy

ChessImprover is suitable for a general audience and is not directed at children under 13. We do not knowingly collect personal information from children. If you believe a child has provided us information, contact us and we will address it.

10. Your choices

You can turn off analytics at any time: open Settings and switch off Share anonymous usage data. This is honoured on the web app and in the mobile apps. When it is off, nothing is collected or sent — the analytics service is disabled outright rather than filtered, and on the web the analytics code is never even downloaded. Crash reporting is unaffected.

Because the app uses no account, the simplest way to stop all data collection is to uninstall the app. You can also manage app permissions (such as notifications) and reset device-level identifiers through your device settings.

11. Changes to this policy

We may update this policy as the app evolves. Material changes will be reflected here with a new "Last updated" date.

12. YouTube API Services

Our YouTube channels (@ChessImproverApp and @ChessImproverEspanol) publish daily puzzle videos through an internal publishing tool that uses YouTube API Services. The tool acts only on our own channels: it uploads our own videos and reads our own channels' analytics. It does not access, collect, or store any data about other YouTube users or channels. By using YouTube API Services this tool agrees to the YouTube Terms of Service, and Google's handling of data is described in the Google Privacy Policy. Any OAuth access the tool holds on our own account can be reviewed and revoked at any time via Google security settings.

13. Contact

Questions about this policy: chessimproverapp@gmail.com.