Remind

Inspiration

Managing reminders across multiple devices is fragmented. We wanted a seamless cross-platform solution with real-time sync that delivers a truly native experience on both Android and iOS.

What it does

Remind is a cross-platform reminder app with smart categorisation (Overdue, Upcoming, Missed, Snoozed), flexible scheduling with advanced notifications, snooze functionality, real-time multi-device sync, offline support, and multi-provider authentication (Email, Google, Apple).

How we built it

• Kotlin Multiplatform + Compose Multiplatform for ~90% shared code
• Room Database for local persistence, Firebase Firestore for cloud sync
• MVVM + Clean Architecture with Koin for dependency injection
• Platform-specific: AlarmManager/WorkManager (Android), UserNotifications (iOS)

Challenges we ran into

• Precise notifications across platforms with different scheduling APIs
• Device reboot persistence - implemented BroadcastReceiver to reschedule alarms
• Offline-first sync with optimistic updates and exponential backoff retry
• Cross-platform datetime handling with timezone consistency

Accomplishments that we're proud of

• Smart categorisation algorithm with real-time 30-second refresh
• Reliable background sync with conflict resolution
• Seamless offline-to-online data recovery

What we learned

Kotlin Multiplatform is production-ready. Compose Multiplatform accelerates cross-platform UI development. Platform nuances (Doze mode, iOS background limits) require thoughtful native solutions.

What's next for Remind

Widgets, WearOS/Apple Watch support, location-based reminders, collaboration features, and calendar integration.

Built With

• android
• android-studio
• firebase
• firestore
• ios
• jetpackcompose
• kotlin
• room
• swift