Privacy Policy

1. Introduction

ChessMaster ("we," "our," or "us") is committed to protecting your privacy. This Privacy Policy explains how we collect, use, disclose, and safeguard your information when you use our chess-improvement analytics and coaching application and services.

2. Information We Collect

2.1 Account Information

When you sign in with Google (or, optionally, Apple), we collect:

• Your name and email address
• Your profile image, where provided by the sign-in provider
• Basic account settings (goal rating, preferred time class, coaching style)

We never receive or store your Google or Apple password — authentication is handled entirely by those providers.

2.2 Chess.com Game Data

When you link a chess.com username, we retrieve and store data from chess.com's public API, including:

• Your public game records (moves, results, ratings, openings, time controls, timestamps)
• Your public chess.com profile information (username, ratings)

We only access data that chess.com makes publicly available. We never ask for your chess.com password, and linking your username does not give us access to your chess.com account.

2.3 Analysis & Coaching Data

From your games we compute and store:

• Per-move engine evaluations produced by Stockfish (centipawn loss, move classifications, evaluation graphs)
• Aggregated analytics (accuracy, blunder patterns, opening and time-management statistics)
• AI-generated coaching text, lessons, training programs, and your Tutor chat history

3. How We Use Your Information

We use your information to:

• Provide and improve our chess analytics and coaching services
• Analyse your games and surface your weaknesses, blunder patterns, and opening performance
• Generate personalised coaching, lessons, and an evolving training program
• Power the Tutor chat, which answers questions using your own game data
• Display your progress, ratings trend, and analytics
• Ensure security and prevent abuse

4. Data Sharing and Disclosure

We do not sell your personal information. We share data only in the following circumstances:

• AI processing: Game statistics and coaching prompts are sent to Anthropic's Claude API to generate coaching text. This data is processed to provide the service and is not used to train third-party models.
• Service providers: Infrastructure providers (such as our database and hosting) that process data on our behalf to run the app.
• Legal requirements: When required by law or to protect our rights and safety.

5. Data Security

We implement industry-standard security measures to protect your data, including encryption in transit, secure authentication, and access controls. However, no method of transmission over the internet is 100% secure.

6. Your Rights

You have the right to:

• Access your personal data
• Correct inaccurate data
• Delete your account and data
• Unlink your chess.com username
• Export your data

To exercise these rights, please contact us through our Support & Help page.

7. Data Retention

We retain your data for as long as your account is active or as needed to provide services. When you delete your account, we will delete or anonymise your personal data within 30 days, except where we are required to retain it for legal purposes.

8. Children's Privacy

Our services are not intended for users under the age of 13. We do not knowingly collect personal information from children under 13. If you believe we have collected information from a child under 13, please contact us immediately.

9. Changes to This Policy

We may update this Privacy Policy from time to time. We will notify you of any material changes by posting the new policy on this page and updating the "Last updated" date. Your continued use of our services after changes become effective constitutes acceptance of the updated policy.

10. Contact Us

If you have questions about this Privacy Policy or our data practices, please contact us through our Support & Help page or email us at general@ashishgupta.co.uk.