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docs/thijooree/15-settings-security.md

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+# Settings — Security
+
+Controls the app lock method, biometric options, auto-lock timeout, and screenshot restriction.
+
+---
+
+## Fragment — `SettingsSecurityFragment`
+
+---
+
+## Change Lock Method
+
+A **Change PIN** or **Change Pattern** button (label reflects current method) opens the security setup flow (same `SecuritySetupFragment` as onboarding) in change-mode. The user must first authenticate with the current PIN/pattern/biometric before the new one is accepted.
+
+---
+
+## Biometrics
+
+A toggle to enable or disable biometric authentication (fingerprint / face — `BIOMETRIC_WEAK`).
+
+- When enabled, `BiometricPrompt` is offered at the lock screen as an alternative to PIN/pattern
+- A secondary toggle controls whether biometrics are also required for transfer confirmation
+
+Biometric availability is checked via `BiometricManager.canAuthenticate()`. The toggle is disabled with an explanatory message if the device has no enrolled biometrics.
+
+---
+
+## Auto-Lock Timeout
+
+A radio group or dropdown to set the inactivity timeout:
+
+| Option | Timeout |
+|---|---|
+| 30 seconds | 30 s |
+| 1 minute | 60 s |
+| 3 minutes | 180 s |
+| 5 minutes | 300 s |
+| Never | Disabled |
+
+The selection is stored in `SharedPreferences` and read by `HomeActivity` on each timer reset.
+
+---
+
+## Screenshots
+
+A toggle for `FLAG_SECURE` on `HomeActivity`'s window.
+
+- **On (default)**: screenshots and screen recording are blocked system-wide while the app is in the foreground
+- **Off**: screenshots are allowed
+
+The lock screen always has `FLAG_SECURE` regardless of this setting.
+
+---
+
+ 
+
+---
+
+[← Settings](14-settings.md)     **Next →** [Settings — Appearance](16-settings-appearance.md)