📅 Last updated: April 2026 · 🏢 Nalkudil Studio · 📧 nalkudilstudio@gmail.com
Our commitment: Chess Master for Kidz is built for children — so privacy is our highest priority. The app works fully offline. We collect no personal data. We show no ads. Your child's learning journey stays entirely on their device.
Chess Master for Kidz stores the following information locally on your device only. This data never leaves the device and is never accessible to Nalkudil Studio.
| Data | Purpose |
|---|---|
| Player name | Personalising DR's messages and greetings |
| Skill level selection | Setting DR's starting difficulty |
| Game results and rating | Showing progress on the Profile screen |
| Puzzles solved and streaks | Tracking learning progress and unlocking tiers |
| Parental control settings | Screen time and access control (PIN stored as SHA-256 hash) |
| App preferences | Remembering sound and display settings |
We do not collect names, email addresses, location data, device identifiers, advertising IDs, crash reports, photos, camera or microphone access, or any data from children under 13.
Chess Master for Kidz is 100% offline. All puzzles, lessons, and games work without any internet connection. The app makes zero network requests and does not communicate with any external server.
This app is designed for children aged 6–14. We take their privacy more seriously than anything else.
Built-in parental controls are accessible from Settings → Parental Controls.
| Feature | Description |
|---|---|
| 🔒 PIN Protection | 4-digit PIN to restrict settings access. Stored as a one-way SHA-256 hash — never recoverable. |
| ⏱️ Screen Time Limits | Set daily play time limits. DR reminds your child when time is up. |
| 📊 Progress Dashboard | Weekly activity, rating trends, puzzles solved — visible only to parents. |
| 👆 Fingerprint Unlock | Biometric alternative to PIN, processed entirely on-device. |
| Component | Licence | Source |
|---|---|---|
| Stockfish Chess Engine | GPL v3 | stockfishchess.org |
| Lichess Puzzle Database | CC0 (Public Domain) | lichess.org |
| Jetpack Compose, Room, Hilt | Apache 2.0 | developer.android.com |
Sound effects courtesy of Lichess.org (CC BY-NC 4.0).
To delete all data, simply uninstall the app. No data is stored remotely, so uninstalling removes everything completely and permanently.
If we update this policy, the new version will be published at this URL and reflected in the next app update. We will not retroactively reduce protections without appropriate notice.
Questions? We're a small family studio — every message is read personally.