Privacy Policy

App: ChuuiCroc  ·  Last updated: 21 June 2026

1. What ChuuiCroc does

ChuuiCroc is a notification app for WaniKani (a third-party Japanese learning service). A server operated by the developer periodically checks the WaniKani API on your behalf and sends a push notification to your device when reviews or lessons are available.

2. Data stored on your device

The app stores the following data locally on your device:

• WaniKani API token — stored in the Android Keystore (Android) or iOS Keychain (iOS), the platform's secure credential storage.
• Firebase Cloud Messaging token — a device-specific identifier used to deliver push notifications. Generated by Google's Firebase service; it does not contain personal information.
• App settings — notification preferences, check interval, quiet-hours schedule, and theme. Stored in standard app preferences (SharedPreferences / NSUserDefaults). Not sensitive.
• Diagnostic logs — an in-memory ring buffer of recent app events (last 500 entries), used for troubleshooting. These are never sent anywhere automatically; you can view them in Settings and optionally include them when sending feedback.

3. Data stored on the server

When you register with ChuuiCroc, the following data is sent to and stored on the ChuuiCroc push notification server:

• Firebase Cloud Messaging device token — used to deliver push notifications to your device.
• WaniKani API token — used to check the WaniKani API for pending reviews and lessons on your behalf. The app requires a read-only token with no write permissions.
• Platform — whether your device is Android or iOS, so the server sends notifications via the correct channel.
• Notification preferences — check interval, lesson notifications toggle, and quiet-hours schedule.
• Poll state — the set of WaniKani subject IDs from the last check and the next review time, used to avoid sending duplicate notifications.

This data is stored in a SQLite database on the server. It is used solely to deliver notifications and is not shared with any third party. If you unregister (by deleting your API key in the app) or if your device has not opened the app for 30 days, your data is automatically removed from the server.

4. Network requests

The app communicates with the following services over HTTPS:

• ChuuiCroc push server (chuuicroc.rdacted.com) — to register your device, sync notification preferences, send heartbeats, and request test notifications. All requests are authenticated with a shared app secret.
• WaniKani API (api.wanikani.com) — at registration time, the app validates your API token directly with WaniKani. Ongoing polling is performed by the server, not the app.
• Firebase Cloud Messaging (Google) — the app receives a device token from FCM at startup. The server uses FCM (Android) or APNs (iOS) to deliver push notifications.

WaniKani's own privacy policy governs how they handle your data: wanikani.com/privacy. Google's Firebase privacy information: firebase.google.com/support/privacy.

5. Data we do not collect

• No analytics or usage tracking
• No crash reporting services
• No advertising identifiers
• No personal identifiers (name, email, account ID)
• No location data
• No contacts, camera, microphone, or any other sensitive permission

6. Data retention and deletion

You can delete your data from the server at any time by deleting your API key in the app's Settings screen. This sends an unregister request to the server, which immediately removes your device record.

Devices that have not opened the app for 30 days are automatically removed from the server database. Push tokens that become invalid (e.g. after uninstalling the app) are removed when the server detects the token is no longer valid.

7. Permissions explained

Android:

• INTERNET — required to contact the ChuuiCroc server, WaniKani API, and Firebase.
• POST_NOTIFICATIONS — required on Android 13+ to display notifications.
• VIBRATE — used when a notification is shown.
• RECEIVE_BOOT_COMPLETED — allows the app to re-register for push notifications after a device restart.

iOS:

• Notifications — required to display review and lesson alerts.
• Background App Refresh — allows the app to refresh its push token and sync with the server in the background.

8. Children's privacy

ChuuiCroc is not directed at children under 13 and does not knowingly collect any information from them.

9. Changes to this policy

If the privacy practices of the app change materially, this page will be updated with a new date at the top. Continuing to use the app after a change constitutes acceptance of the updated policy.

10. Contact

Questions about this privacy policy can be sent to chuuicroc@rdacted.com.