Privacy Policy for Only Opens

This Privacy Policy explains how Only Opens ("we", "our", or "us"), developed by Latent Divergence, collects, uses, and protects information when you use the Only Opens mobile application (the "App"). We are committed to protecting your privacy and being transparent about our practices.

By using the App, you agree to the terms of this Privacy Policy.

1. Information We Collect

1.1 Information Stored Locally on Your Device

Only Opens stores the following data on your device only. This data does not leave your device except as described in Section 2 (Third-Party Services).

• Opening study progress — which chess openings you have studied, your spaced repetition intervals, ease factors, and review timestamps. This data powers the spaced repetition algorithm that schedules your reviews.
• App preferences — your chosen board theme (colour palette) and whether you have completed the first-launch tutorial.
• Imported PGN data — if you choose to import chess games from a PGN file, the move sequences from those games are stored locally for repertoire analysis.

1.2 Information We Do Not Collect

We do not collect:

• Your name, email address, phone number, or any account credentials
• Your precise or approximate location
• Your contacts, calendar, or media files
• Payment information of any kind
• Any biometric data

We do not operate servers that receive your personal information, and we do not create user accounts.

2. Third-Party Services

The App integrates two third-party services that may process data separately from us.

2.1 Google AdMob

The App displays advertisements served by Google AdMob (Google LLC). AdMob may collect the following to personalise and serve ads:

• Advertising ID (Android Ad ID) and device identifiers
• IP address and approximate location derived from IP
• Device type, operating system version, and language settings
• Ad interaction data (impressions, clicks)

AdMob's data practices are governed by Google's Privacy Policy.

Opting out of personalised ads: You can opt out at any time via device Settings → Google → Ads → Opt out of Ads Personalisation (wording may vary by Android version).

2.2 Stockfish Online API

When you use the analysis or AI opponent features, the App sends the current chess position in FEN notation to the public Stockfish Online API at stockfish.online. No personal information is included — only the board position itself.

FEN strings contain no identifying information (e.g. rnbqkbnr/pppppppp/8/8/4P3/8/PPPP1PPP/RNBQKBNR b KQkq e3 0 1). These requests are subject to Stockfish Online's own terms.

3. How We Use Information

The locally stored data described in Section 1.1 is used solely to:

• Schedule and present your spaced repetition review queue
• Display your study statistics (openings mastered, daily streak, reviews due)
• Remember your board theme preference between sessions
• Export your studied repertoire to a PGN file on request

We use this information for no other purpose.

4. Data Sharing

We do not sell, rent, trade, or otherwise share your personal data with any third party, except:

• As required by law — if compelled by a valid legal process, court order, or governmental authority
• Third-party SDKs — as described in Section 2 (Google AdMob, Stockfish Online API), which operate under their own privacy policies

5. Data Retention and Deletion

All study data is stored in a local SQLite database on your device. You can delete this data at any time in two ways:

• In-app reset — go to the Profile tab, scroll to "Reset Training Data", and tap Reset Now. This immediately and permanently deletes all spaced repetition progress.
• Uninstall the App — uninstalling removes all locally stored data from your device.

We have no ability to access or delete data stored on your device from our end.

6. Children's Privacy

The App is not directed at children under the age of 13 (or the applicable minimum age in your jurisdiction). We do not knowingly collect personal information from children. If you are a parent or guardian and believe your child has provided information through the App, please contact us at hello@latentdivergence.com and we will take appropriate steps.

7. Your Rights (EEA, UK, and California Residents)

If you are located in the European Economic Area, United Kingdom, or California, you have certain rights regarding your personal data:

• Right to access — you can view all data the App stores via the in-app statistics screen.
• Right to deletion — you can delete all locally stored data as described in Section 5.
• Right to opt out of personalised advertising — as described in Section 2.1.

Because we do not operate servers that hold your personal data, all data is on your device and under your control. For questions about AdMob's GDPR or CCPA practices, please refer to Google's Privacy Policy.

8. Security

We rely on Android's built-in application sandboxing to protect locally stored data. The App's database is not backed up to external services (android:allowBackup="false"). Data sent to the Stockfish Online API is transmitted over HTTPS.

While we take reasonable precautions, no method of electronic storage or transmission is 100% secure.

9. Changes to This Policy

We may update this Privacy Policy from time to time. When we do, we will update the Last Updated date at the top of this document. Material changes will be notified via an in-app notice. Continued use of the App after any changes constitutes acceptance of the revised policy.

10. Contact Us

If you have any questions, concerns, or requests regarding this Privacy Policy, please contact us at:

Email: hello@latentdivergence.com

Website: onlyopens.app