Privacy Policy
01 Who we are
FriendLock is an independent Android app designed and published by sayne.design ("we", "us"). FriendLock is an app-lock you set on your own phone; unlocking a protected app requires approval — a 6-digit code or a remote tap — from another phone you have deliberately paired with. For the purposes of data-protection law, sayne.design is the data controller for the limited data described below, and Google (Firebase) acts as our processor.
02 What we collect & why
FriendLock works without you creating an account or giving us any personal identity. The data we process exists only to make peer-approved unlocking work. Here is the complete list:
| Data | What it is | Why we need it |
|---|---|---|
| Anonymous auth ID | A random Firebase Anonymous Authentication UID created on first launch. Not linked to a name, email, or Google account. | To authenticate your device to the backend without you signing in. |
| Device ID | A random, app-generated identifier stored locally and on the backend. | To address unlock requests and approvals to the correct phone. |
| Push token (FCM) | A Firebase Cloud Messaging registration token for your device. | To deliver unlock_request and unlock_approved notifications. |
| Pairing links | Which device IDs are paired with which, created when you scan a pairing QR code. | To know which phones are allowed to approve each other. Pairing is mutual and visible on both devices. |
| One-time-code secret | An RFC 6238 (TOTP) secret. Stored only on the approver's phone and on our backend — never on the locked phone. | So the server can verify a typed code (verifyOtp) without the locked device ever being able to generate one. |
| Unlock events & grants | Transient records of an unlock request, its approval/denial, and the resulting time-boxed grant and its expiry. | To route an approval back to the locked phone and end the grant when it expires. |
03 What stays on your device
Some information never leaves your phone. It is stored in the app's local database (Room) and preferences (DataStore) and is not uploaded to us:
- Your list of protected apps — which apps you chose to lock lives only on your device.
- App-usage signals used for detection — the accessibility/usage information used to notice when a protected app opens is processed on-device, in real time, to draw the lock overlay. It is not transmitted to us or to your paired devices.
- Local settings — grant duration, spoken-feedback preferences, and similar options.
04 What we never collect
- Your name, email address, phone number, or any Google account details.
- Your contacts, photos, location, or microphone/camera content. (The camera is used on-device only to scan a pairing QR code; no images are stored or sent.)
- The content of your apps, messages, or browsing activity.
- Third-party advertising or analytics identifiers — FriendLock contains no ad SDKs and no third-party analytics.
05 Permissions, explained
FriendLock requests a few sensitive Android permissions. Each has a single, specific purpose:
| Permission | What it's for |
|---|---|
| Accessibility service | To detect when a protected app comes to the foreground and to provide genuine spoken-feedback (text-to-speech) for lock state. Accessibility data is used on-device for detection only and is never recorded or transmitted. |
| Display over other apps | To draw the lock screen overlay on top of a protected app. |
| Usage access | A fallback method of detecting the foreground app where the accessibility event is unavailable. |
| Notifications | To show unlock requests and approval results, and to run the lock service reliably. |
| Camera | Used only to scan a pairing QR code. No photo is captured, stored, or uploaded. |
FriendLock is a self-restriction / digital-wellbeing tool for people who pair by mutual consent. It is not designed or marketed to monitor or control another person's device without their knowledge.
06 Who we share it with
We do not sell your data and we do not share it for advertising. The data above is processed on our behalf by:
- Google Firebase (Google LLC / Google Ireland Ltd.) — providing Anonymous Authentication, Cloud Firestore, Cloud Functions, and Cloud Messaging. Google processes this data as our service provider under its own security and privacy terms.
- Google Play — if you install via the Play Store, Google processes your install and (optionally) crash data under its policies. FriendLock does not receive your Play identity.
We may disclose data if required by law, or to protect the rights, safety, or property of users or the public.
07 Retention & deletion
- Unlock events and grants are short-lived and are cleared once a grant expires or shortly after.
- Pairing links and the code secret persist while a pairing is active. Unpairing a device, or uninstalling the app, removes the relationship and the associated secret from active use.
- On-device data (protected-app list, settings) is deleted when you uninstall the app or clear its storage.
- To request deletion of backend records associated with your device ID, contact us (see below) — note that with anonymous auth we identify your data only by the random IDs your app holds.
08 How we protect it
Data in transit is encrypted (HTTPS/TLS). Backend access is governed by Firebase Authentication and Firestore security rules so a device can only read and write its own pairing and unlock data. The code secret is verified server-side by a Cloud Function so the locked phone never holds it. No system is perfectly secure; as described on our homepage, FriendLock is an accountability tool and makes tampering visible rather than impossible.
09 Children & family use
FriendLock is commonly used in a parent/child arrangement, where a child locks apps on their own phone and a parent approves unlocks. We do not knowingly collect personal information from children, and FriendLock does not require or request any. Because the app uses anonymous authentication and stores no names or contact details, the data we hold cannot directly identify a child. Where a minor uses FriendLock, a parent or guardian should set it up and consent on their behalf. If you believe a child has provided us with personal information, contact us and we will delete the associated records.
10 Your rights
Depending on where you live (e.g. the EEA/UK under GDPR, or California under the CCPA/CPRA), you may have rights to access, correct, delete, or restrict processing of your personal data, and to object to certain processing. Because FriendLock holds only pseudonymous device-linked data and no contact identity, exercising some rights may require information your app stores locally to locate the records. We do not sell or "share" personal information as those terms are defined under California law. To make a request, contact us below.
11 International transfers
Firebase may process and store data on Google infrastructure located outside your country, including the United States. Where required, such transfers rely on appropriate safeguards such as the European Commission's Standard Contractual Clauses, as implemented by Google.
12 Changes & contact
We may update this policy as FriendLock evolves (for example, the planned v2 features such as signed offline approvals). We'll change the effective date above and, for material changes, surface a notice in the app. Questions, requests, or concerns:
- Email: privacy@sayne.design
- Studio: sayne.design — an independent Android app studio