NoxDiary

Unlike cloud-based journaling apps, NoxDiary is local-first: every entry lives on the device, encrypted with AES-256 before storage, behind biometric or pattern authentication with a configurable auto-lock. Encryption keys live in the platform keychain — iOS Keychain and Android Keystore — rather than in application storage, which is the distinction between encrypting data and merely obfuscating it.

Built for actually using it

A rich text editor with Markdown support and tagging handles the writing; edit history with diff highlighting lets users see how a thought changed over time. Mood tracking spans five levels, and FL Chart renders trends across weeks, months and years alongside streak counters, total word counts and mood distribution. A dedicated gratitude journal and a distraction-free focus mode round out the wellness side.

The architecture is textbook three-layer — presentation widgets and Riverpod notifiers, a domain layer of entities and repository interfaces, and a data layer implementing those interfaces over Hive and secure storage. Code generation via Freezed keeps the models immutable. Optional encrypted Google Drive backup and full data export exist so that choosing this app is not a commitment you cannot reverse.