Privacy Policy — Mindstack
Last updated: 20 June 2026
Mindstack ("the app") is a 100% offline, local-only personal notes /
"second brain" application. This policy explains what the app does and
does not do with your information.
Summary
Mindstack does not collect, transmit, sell, or share any personal data.
Everything you create stays on your device. The released app has no
internet permission and makes no network connections.
Data We Store (On Your Device Only)
All content you create — notes, ideas, reminders, voice recordings,
and any backups you export — is stored locally on your device in a
private SQLite database at com.brainvault.offline.
This data:
- Never leaves your device.
- Is not sent to us or to any third party.
- Is not accessible to other apps.
- Is not backed up to the cloud by the app (Android auto-backup is disabled).
Device Permissions
The app may request the following permissions, each used only for its
stated on-device feature:
-
Notifications — to show your local reminders.
-
Microphone (Record Audio) — only when you record a voice note.
Recordings are saved locally and never uploaded.
-
Biometrics (Fingerprint/Face) — optional, to unlock the app.
Biometric data is handled entirely by the Android system; the app
never sees or stores it.
-
Vibrate / Wake Lock / Receive Boot Completed — to deliver
reminders reliably, including re-arming them after a device restart.
The released app does not request the Internet permission.
Security
- App-lock PINs are stored only as a SHA-256 hash, never in plain text.
- Optional encrypted backups are protected using your PIN.
- Biometric unlock relies on your device's secure biometric APIs.
Because all data is stored locally, protecting your device (screen lock,
encryption, physical security) is the primary safeguard for your data.
If you uninstall the app or wipe its data, your content is permanently
deleted and cannot be recovered by us.
Children's Privacy
The app does not collect any data from anyone, including children.
Changes to This Policy
If this policy changes, the updated version will be published at the
same URL with a new "Last Updated" date.
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