Chap
An Android budgeting app that automates entry while keeping you in full control.
Chap is a native Android envelope-budgeting app built to run itself - CSV imports and categorization rules reduce repetitive manual entry, and only genuinely ambiguous cases surface for a decision. Everything else gets filed without you ever touching it.
Categorization rules are set once and applied automatically after that, so the same decision never has to be made twice. Everything stays local by default, encrypted at rest, with encrypted backups tied to the original installation's Keystore key. These backups cannot restore data after uninstalling the app or on another device.
Built natively for Android - Kotlin, Jetpack Compose, and Material 3. Dependency injection is wired through Koin, and the whole app sits behind a biometric gate.
Data stays local-first and encrypted at rest, with Room running on a SQLCipher database and backups sealed with AES-GCM keys held in the Android Keystore. The CSV pipeline sniffs headers, stages drafts for human review, and auto-tags transactions through user-defined matching rules.
Every screen was implemented against a hand-made HTML mock, so the visual contract is versioned like code.
Friction is the enemy
Every budgeting app I'd used added friction instead of removing it. I wanted something to set and forget, fully automated, with analytics that were actually intuitive and informative. So I built it on a local-only philosophy from the start, and wrapped it in a calm, polished purple interface, because managing money should feel easy.
