Privacy Policy - Dinig

1) Who we are

Dinig is provided by Saifullah Ahad ("we", "us", "our"). Website: https://saifullah.ai.

2) What Dinig does

Dinig lets you train one Android phone to recognize selected sounds and send an encrypted cue to a second paired phone. It is an awareness aid, not an emergency alarm, medical device, fire-safety system, or replacement for certified alerting equipment.

3) Microphone processing and recordings

Dinig requests RECORD_AUDIO permission. The microphone is used only when you explicitly record a training example or turn on listening. Short audio windows are processed in memory on your device to create or compare numeric sound fingerprints.

Dinig does not save, upload, transmit, or share raw audio or audio recordings. Training buffers are discarded after the fingerprint is calculated.

4) Data stored on your device

Dinig stores your cue names, numeric fingerprints, thresholds, enabled settings, recent cue events, review choices, private pairing material, and the last received-event cursor in app-private local storage. You can delete cues, clear history, remove a device link, clear app storage, or uninstall the app.

5) Paired-device relay

If you choose to pair two phones, Dinig uses Firebase Authentication to create a random anonymous device identifier and Cloud Firestore to coordinate the link. The service processes:

• a random pair identifier and temporary six-digit discovery code;
• up to two anonymous device identifiers and connection status;
• an encrypted cue payload, sender identifier, sequence number, and event time.

The cue name and match confidence are encrypted on the sending phone with AES-GCM before upload. The transport key is wrapped from the temporary code and used by the paired phones. Firestore security rules limit each pair to its anonymous members. A pairing code is intended for use within ten minutes.

6) How information is used

Data is used only to provide personal sound matching, paired-device cue delivery, receiver alerts, missed-event recovery, local history, and controls requested by you. We do not use it for advertising, profiling, marketing, or data brokerage.

7) Service providers and sharing

Google Firebase provides anonymous authentication and Cloud Firestore hosting. Google may process technical information required to operate those services under its terms and privacy commitments. We do not include advertising, analytics, social networking, or third-party tracking SDKs, and we do not sell personal data.

8) Permissions

• Microphone: personal sound training and user-started listening.
• Notifications: active-listening status and paired cue alerts.
• Internet/network state: anonymous sign-in, pairing, and encrypted cue delivery.
• Foreground service, wake lock, and vibration: user-visible listening/receiver modes and cue vibration.

9) Retention and deletion

Local data remains until you delete it, clear app storage, or uninstall Dinig. Cloud pair and event data remain while a link is used or until a member removes the link. You can use Privacy & control → Remove paired-device data inside Dinig to delete the encrypted event documents, pairing metadata, and that device’s anonymous Firebase identity. You may also request deletion help by emailing us.

10) Security

Dinig uses Android app-private storage, authenticated Firestore access, restrictive two-member security rules, an expiring discovery code, PBKDF2 key wrapping, and AES-GCM cue encryption. No method of storage or transmission can be guaranteed completely secure.

11) Children's privacy

Dinig is a general accessibility utility and is not directed to children under 13. It does not provide profiles, chat, public sharing, or user-generated community content. We do not knowingly collect personal information from children.

12) International processing

Firebase data may be processed in the Firestore region configured for Dinig and by Google facilities in other countries. By choosing paired-device features, you understand that encrypted cue-service data may be processed outside your country.

13) Changes to this policy

We may update this policy when Dinig changes. The current version will remain at https://privacy.saifullah.ai/dinig.html with a revised effective date.

14) Contact

Questions or deletion requests: Saifullah Ahad
Email: [email protected]
Website: https://saifullah.ai
Location: Dhaka, Bangladesh