Calmanac
An offline-first calendar, day planner and alarm app for iOS and Android.
Self-initiated prototype — built and running, but not published. The results below are the targets it was built against, not measured figures.
What made it hard
Planners assume a day is a grid of equal hours. It is not — attention rises and falls, and a block placed at the wrong point on that curve is a block that quietly does not happen. The other problem is trust: a calendar knows everything about you, and most of them ship it to a server.
How it works
Everything is computed on the device from one stored document, and nothing is sent anywhere. A learned energy curve, sharpened by focus check-ins, scores the free slots, so the scheduler proposes placements you accept one at a time instead of a timetable you have to undo. The domain logic is kept clear of React, so the same functions feed the day grid, the week overlay and the weekly recap.
- Expo
- React Native
- TypeScript
- expo-router
- AsyncStorage
- react-native-svg
- A plan that survives contact with a real day
- Alarms that ring with the app closed, on both platforms
- No account, no sync, no server — the data never leaves the device