Daybook: Offline-First Android Daily OS
A 100% offline personal productivity workspace with on-device OCR and private encrypted storage.
Daybook is a private Android operating system built with Jetpack Compose and hardware-backed SQLCipher database encryption. Engineered with a strict zero-cloud architecture: all tasks, journals, digital passes, and notes stay entirely on-device with zero network permissions. Features reboot-resilient reminders, on-device OCR for scanning documents, and private morning briefings.
The Problem
Modern productivity apps leak sensitive notes to cloud servers, require continuous internet connections, and consume excessive battery with background telemetry.
The Approach & Implementation
Engineered a private Android architecture with SQLCipher encrypted storage, Room ORM, CadenceEngine reboot-resilient alarm dispatching, on-device ML Kit OCR, and Jetpack Compose liquid glass UI.
Measurable Outcome
Passed 197 automated test suites with 0 network permissions required, zero battery drain on idle, and instant local search across encrypted logs.