Privacy Policy

Last updated: June 2026

1. Information We Collect

We collect information you provide directly: your email address and password when you register. We also collect usage data such as lessons completed, XP earned, and puzzle results to power your progress tracking. This policy is available in other languages upon request — contact chessmasterapp01@gmail.com.

2. How We Use Your Information

We use your information to provide and improve the Service, process payments, send account-related emails (e.g. password reset), and personalise your learning experience. We do not sell your personal data to third parties.

3. Authentication and Data Storage

Authentication and database storage are handled by Supabase, which stores data on servers in the European Union. Your password is never stored in plain text — it is hashed by Supabase Auth before storage. You may also sign in using your Google account via Google OAuth. When you do, Google shares your email address and profile information with us. No password is stored by us in that case; authentication is managed by Google.

4. Payment Processing

Payments are processed by Dodo Payments, a third-party payment provider. We do not store your card number or payment details. Dodo Payments's privacy policy governs how your payment data is handled.

5. Cookies and Local Storage

We use browser localStorage to store your sound preference (muted/unmuted). We also use PostHog, an analytics service, which stores data in localStorage and cookies to track pageviews and record anonymised session behaviour (all form inputs are masked). This helps us understand how users interact with the Service and improve it. We do not use advertising cookies.

6. Data Retention

We retain your account data for as long as your account is active. If you delete your account, your personal data will be removed within 30 days, except where retention is required by law.

7. Your Rights

You have the right to access, correct, or delete your personal data. Under the Digital Personal Data Protection Act, 2023 (India), you may also nominate a person to exercise your rights on your behalf. To exercise any of these rights, contact our Grievance Officer at chessmasterapp01@gmail.com. We will respond within the timeframes required by applicable law.

8. Children's Privacy

The Service is not directed to children under the age of 18. In accordance with the Digital Personal Data Protection Act, 2023 (India), we do not knowingly collect personal data from minors under 18 without verifiable parental consent. If you believe a minor has provided us with personal information, please contact us at chessmasterapp01@gmail.com and we will delete it promptly.

9. Security

We implement industry-standard security measures including HTTPS, hashed passwords, and row-level security on our database. No method of transmission over the internet is 100% secure, and we cannot guarantee absolute security.

10. Third-Party Services

The Service integrates with Supabase (auth and database), Google OAuth (social sign-in), Dodo Payments (billing), PostHog (analytics), Lichess, and Chess.com. When you use the Game Review feature and submit a Lichess or Chess.com game URL, that game's data is fetched from their public APIs. These services have their own privacy policies. We are not responsible for their privacy practices. Where required by applicable law, we have entered into Data Processing Agreements with our sub-processors.

11. Public Leaderboards and Profiles

Battle and puzzle leaderboard rankings are publicly visible. Your display name and rating may be shown to other users on these leaderboards. If you wish to have your information removed from public leaderboards, you may delete your account.

12. Grievance Officer (India)

In accordance with the Digital Personal Data Protection Act, 2023, our Grievance Officer for India-related privacy matters can be contacted at chessmasterapp01@gmail.com. We will acknowledge your grievance within 48 hours and resolve it within 30 days of receipt.

13. How to Access This Policy

This Privacy Policy is accessible at all times. On desktop, find it in the sidebar at the bottom of the navigation. On mobile, go to Settings (bottom navigation bar) and tap the Privacy Policy link. It is also shown at sign-up before you create an account. You can always reach it directly at chessmasterapp.com/privacy.

14. Changes to This Policy

We may update this Privacy Policy from time to time. We will notify you of significant changes by posting a notice on the Service or emailing you. Continued use of the Service after changes constitutes acceptance.

15. Contact

For privacy-related questions or requests, contact us at chessmasterapp01@gmail.com.