Privacy Policy
Handini ("the App", "we", "us", "our"), operated by Tranquil Mind Technology JSC, respects your privacy. This Privacy Policy explains what information we collect, how we use and share it, and the choices and rights you have. By using the App, you agree to this Policy.
Handini lets you cast glowing AR magic effects with your hands: it uses your device camera to recognize your hand gestures, hand seals, and simple face cues, draws effects that follow them, and lets you record the result as a video. You do not need to create an account to use the App.
1. Information we collect
Processed only on your device (not collected by us)
- Camera. With your permission, the App opens your front or rear camera to recognize your hands, your face position (for cues such as closing your eyes or opening your mouth), and the outline of your body (for the optional background-separation effect). All recognition runs entirely on your device using on-device machine-learning models bundled with the App (Google MediaPipe Hand Landmarker, Face Landmarker, and Selfie Segmenter, plus a small on-device hand-seal classifier). Camera frames and the hand, face, and segmentation data computed from them exist only in device memory while the camera is active and are not uploaded, stored on our servers, or shared with anyone. We do not use the camera to identify you, and we do not create, store, or transmit facial-recognition or other biometric templates.
- Photos you choose. Two effects (Birthday Cake and Draw Image Region) let you pick photos through your device's system photo picker. The App does not request access to your whole photo library; it receives only the photos you select, uses them on your device to render the effect, and does not upload them.
- Videos you record. When you tap Record, the App captures its own camera-effect view (using Android screen-capture / media-projection, limited to the App's own window) and, if you chose one, mixes in a music track bundled with the App. The App does not record microphone audio. Recordings are saved in the App's Collection on your device and, if you choose, to your device's Movies/gallery folder. We never receive them. If you use the Share button, the video is handed to the app you pick through your device's share sheet, under that app's own privacy policy.
- Settings and progress. Your language, onboarding status, notification preference, hand-seal training progress, scores, and the list of your recordings are stored locally on your device and are not sent to us.
- Notifications. If you allow notifications, the App schedules local reminder notifications on your device. They are generated on the device; we do not collect a push-notification token.
Collected automatically (sent to our service providers)
When you use the App, the following data is transmitted to Google services that act as our service providers:
- App activity and usage data — screens viewed, effects used, features used, session information, and similar app interactions (Google Firebase Analytics).
- Device and app identifiers — the Firebase app-instance ID, a Crashlytics installation ID, and, where available on your device, the Android advertising ID, together with device model, operating-system version, app version, language, and similar technical information.
- Approximate location — a coarse location (country or region) derived from your IP address by Firebase Analytics. We do not request or collect precise (GPS) location, and the App has no location permission.
- Crash logs and diagnostics — crash reports, stack traces, and device state at the time of a crash (Google Firebase Crashlytics).
We do not collect your name, email address, phone number, contacts, microphone audio, your photo library, your recordings, or precise location. The App does not display advertising and does not offer in-app purchases at this time.
2. How we use information
- To provide and operate the App, including real-time on-device hand, face, and background recognition, AR effects, and video recording.
- To remember your settings, progress, and recordings on your device.
- To send the local reminder notifications you have allowed.
- To understand how the App is used and to improve its features, effects, and performance (analytics).
- To detect, diagnose, and fix crashes and technical problems.
- To protect the security and integrity of the App and to comply with legal obligations.
3. Third-party services
The App uses the following third-party services, which may receive the data described above:
| Service | Purpose | Data | Privacy policy |
|---|---|---|---|
| Google Firebase Analytics | Usage analytics | App interactions, app-instance ID, advertising ID (where available), device information, approximate location derived from IP | https://firebase.google.com/support/privacy |
| Google Firebase Crashlytics | Crash reporting and diagnostics | Crash logs, diagnostics, installation ID, device information | https://firebase.google.com/support/privacy |
| Google MediaPipe (Hand Landmarker, Face Landmarker, Selfie Segmenter) and LiteRT | On-device recognition of hands, face cues, and background | Runs locally on your device; no camera data is sent to Google or to us | https://policies.google.com/privacy |
Google's general privacy policy: https://policies.google.com/privacy
Advertising ID. The App does not show ads, but Firebase Analytics may read your device's advertising ID for analytics. You can reset it or delete it at any time in your device settings (Android: Settings → Google → Ads, or Settings → Privacy → Ads). Deleting the advertising ID stops it from being used for analytics going forward.
4. How we share information
We do not sell your personal information, and we do not share it for cross-context behavioral advertising. We share information only:
- with the service providers listed in Section 3, which process it on our behalf to provide analytics and crash reporting;
- when required by law, regulation, legal process, or a governmental request, or to protect the rights, property, or safety of our users, us, or others;
- in connection with a merger, acquisition, or sale of assets, subject to this Policy.
When you use the Share button, the App opens your device's share sheet; what you share and with whom is handled by the app you choose and its own privacy policy.
5. Legal bases (EEA/UK — GDPR)
- Legitimate interests — operating the App, keeping it secure, fixing crashes, and improving it through aggregated analytics.
- Consent — camera access, access to the photos you pick, screen-capture permission for recording, and notifications (each granted through your device's permission prompts, which you can withdraw at any time), and analytics where consent is required by local law.
- Legal obligation — where we must process data to comply with the law.
6. Data retention
- Camera frames, hand and face landmarks, and segmentation masks are not retained; they exist only in device memory while the camera is active.
- Photos you pick, videos you record, and your settings and progress remain on your device until you delete them in the App or clear the App's data or uninstall it.
- Firebase Analytics data is retained according to our Firebase retention settings (up to 14 months for user-level data), after which it is deleted or aggregated.
- Crashlytics crash reports are retained for a limited period (currently up to 90 days).
7. Your rights
Depending on where you live, you may have the right to:
- GDPR / UK GDPR: access, correct, delete, or port your personal data; object to or restrict processing; withdraw consent at any time; and lodge a complaint with your local data protection authority.
- CCPA / CPRA (California and other U.S. states): know what personal information we collect, use, and disclose; request deletion and correction; opt out of the sale or sharing of personal information (we do not sell or share it); and not be discriminated against for exercising your rights.
- Other regions (e.g. Brazil's LGPD, Canada's PIPEDA): similar rights of access, correction, deletion, and information.
Because the App has no accounts, we cannot link analytics data to your name. To make a request, email us at contact@tranquilmind.co and include your device model, your advertising ID if you can find it (Android: Settings → Google → Ads), and the approximate dates you used the App so we can locate the related records. You can also stop all data collection at any time by uninstalling the App, delete your recordings in the App's Collection, and revoke the camera, notification, or screen-capture permission in your device settings.
8. Children's privacy
The App is intended for users aged 13 and older and is not directed to children under 13 (or the higher minimum age of digital consent in your country, such as 16 in some EEA countries). We do not knowingly collect personal information from children under 13. If you believe a child has provided us with personal information, contact us at contact@tranquilmind.co and we will delete it.
9. International data transfers
Our service providers (such as Google) may process data in countries other than your own, including the United States. Where required, such transfers are protected by appropriate safeguards, such as the European Commission's Standard Contractual Clauses.
10. Data security
Data sent to our service providers is encrypted in transit using HTTPS/TLS. Camera processing stays on your device. We take reasonable measures to protect information, but no method of transmission or storage is 100% secure.
11. Changes to this Policy
We may update this Privacy Policy from time to time, including if we add advertising or paid features. Material changes will be posted on this page with a new "Last updated" date. Your continued use of the App after changes means you accept the updated Policy.
12. Contact us
Tranquil Mind Technology JSC No. 3, Alley 98, Vu Trong Phung Street, Thanh Xuan Ward, Hanoi City, Vietnam Email: contact@tranquilmind.co
© 2026 Tranquil Mind Technology JSC (@Tranquil Mind Technology JSC). All rights reserved.