Midori Health
Built an offline-first care tracker used by 800 clinicians.
Midori Health provides community healthcare programs in semi-urban Maharashtra. Their clinicians — mostly ASHA workers and field nurses — were tracking patient visits, vitals, and medication adherence in paper registers. The paper registers were being digitised weeks later by a data entry team. By then, the data was stale.
No internet. No data. No insight.
The core constraint: many field sites have intermittent or no connectivity. Any solution that required a live connection would fail in the field. The previous app (a third-party mHealth tool) had been tried and abandoned — clinicians stopped using it after the first month because it failed silently when offline. Trust in the tool was zero. We were rebuilding that trust, not just the software.
Works with no signal. Syncs when it gets one.
Offline-first wasn't a feature — it was the architecture. We used WatermelonDB for local SQLite storage with a custom sync engine that resolves conflicts intelligently (last-write-wins for most fields, merge for append-only fields like notes). The UI was designed with Midori's field team: large tap targets, minimal text input, and a patient-lookup flow that works in under 4 taps from home screen. Training was built into the onboarding — 15 minutes, no manual.
- →WatermelonDB offline-first architecture — works with zero connectivity
- →Custom sync engine with conflict resolution for concurrent edits
- →Patient lookup, vitals entry, medication adherence tracking
- →Visit scheduling and reminder system (local notifications)
- →Supervisor dashboard (web) for programme managers
- →Onboarding flow: 15-minute self-guided setup, no trainer required
- →React Native + Expo — single codebase for Android (primary) and iOS
From paper registers to live data in 11 weeks.
The first cohort of 200 clinicians went live in week 8 of build. Nisha told us the adoption curve was unlike anything they'd seen with previous tools — clinicians were showing the app to each other without being asked. By month 2, daily active use was 3.4× higher than their best previous tool had achieved in its entire lifetime. The paper registers were formally discontinued in month 3.
- →3.4× increase in daily active use vs. previous tool
- →800 clinicians onboarded across two cohorts
- →Paper registers discontinued in month 3 of deployment
- →Data latency: weeks → under 2 seconds on reconnect
- →Sync conflict rate: < 0.1% of records in first 90 days
What they walked away with.
- →React Native mobile app (Android + iOS)
- →Offline-first sync engine (WatermelonDB)
- →Supervisor web dashboard (Next.js)
- →Push notification system
- →Onboarding + training flow
- →GitHub repo (theirs), full documentation
- →Notion handover + sync architecture guide
- →30-day post-launch support
The tools we used.
Weekly Friday demos changed how our team thinks about shipping. We've kept the ritual. Oh, and the app is great.
Nisha K.
CPO, Midori Health