Overview

Adya is a minimal daily task manager: unlimited tasks organized into custom lists, a focused "Today" view, a built-in focus timer, streaks, and a calendar heatmap of completions. It started as a native SwiftUI prototype to validate the product idea quickly on iOS, then was deliberately rewritten from scratch in Expo/React Native once the concept held up — trading a bit of native polish for one codebase across iOS and Android.

Why Rewrite Instead of Port

The SwiftUI version (9 incremental commits: scaffold → multi-list support → design system → calendar → search/reminders → today view → UX pass → accessibility pass) proved the product was worth building further. Rather than maintaining a second, hand-translated Swift/Kotlin codebase for Android, the decision was to rewrite on React Native's New Architecture — accepting short-term rebuild cost for long-term velocity on a single codebase.

Architecture

• State: Zustand store with selectors kept separate from UI components, persisted via AsyncStorage
• Navigation: Expo Router (file-based), mirroring the SwiftUI version's four core tabs — Today, Lists, Calendar, Completed — plus list detail, task edit, focus timer, and settings screens
• Natural-language dates: chrono-node replaces the native version's custom NL date parser for entering tasks like "tomorrow at 5pm"
• Native feel on RN: expo-notifications, expo-haptics, react-native-reanimated/worklets, and react-native-gesture-handler, with native module access wrapped behind a src/lib/ abstraction rather than called directly from screens

Technologies Used

Original prototype: Swift, SwiftUI, Xcode (xcodegen), UserNotifications, a custom natural-language date parser Rewrite: Expo SDK 54, React Native 0.81 (New Architecture), React 19, TypeScript, Expo Router, Zustand, AsyncStorage, chrono-node, react-native-svg

Challenges and Learnings

Rebuilding, not translating: A line-by-line Swift-to-RN port would have carried over UI patterns that don't map cleanly to React Native's layout model. Rebuilding the screens from the store outward, rather than translating file-by-file, kept the RN version idiomatic instead of "SwiftUI wearing a React Native costume." State/UI separation paid off early: Keeping Zustand selectors out of the components made it straightforward to re-implement each screen against the same store contract as the native version's feature set was ported over.

Next Steps

This project doesn't have automated test coverage yet — it's a fast, solo rebuild focused on getting the cross-platform port feature-complete first. The architecture (store isolated from UI, native calls wrapped in src/lib/) is set up to make adding Detox E2E coverage for the core flows — create task, complete task, start focus timer — a contained next step rather than a retrofit.