Building Scalable React Native Apps: Lessons from the Trenches

Architecture that survives year two

Feature folders beat type folders once the app grows:

src/
  features/
    auth/
    home/
    settings/
  shared/
    components/
    hooks/
    api/
  navigation/

State: don't default to Redux

Three state libraries in one app is a smell, not a flex.

Performance checklist

• FlatList for long lists — never ScrollView for 200 items
• Image caching strategy day one
• Hermes on Android where possible
• Profile with Flipper / built-in tools before guessing

Testing pyramid

1. Unit — pure functions, validators
2. Integration — screen + mocked API
3. E2E — signup, pay, core action only

Offline & releases

• Define what works offline (read-only vs queue writes)
• OTA updates policy with Expo if applicable
• Store review buffer in timeline

TL;DR

Consistent structure + boring state choices + list performance = apps you can hand to another team.