Snappy, Not Crappy: An Android Health & Performance Journey
Article Summary
Your Android app might be bleeding users before they even finish launching it. Performance isn't a feature anymore. It's table stakes.
This deep dive breaks down the essential strategies Android engineers use to keep apps snappy and responsive. From cold start optimization to thermal management, it covers the full spectrum of performance work that separates great apps from abandoned ones.
Key Takeaways
- ANR prevention starts with detecting long-running operations on the main thread
- Cold start optimization through lazy loading and deferred component loading
- Maintain 60+ fps by avoiding overdraw and optimizing layout rendering
- Battery optimization via network batching and efficient wake lock management
- Thermal throttling prevention by monitoring device heat and adjusting processing loads
Performance requires continuous profiling, real device testing, and monitoring across eight critical areas from memory management to thermal control.
About This Article
Reddit's Android app had ballooned to over 50MB with features tightly woven together. CI times stretched to hours, and even small changes became risky and hard to test.
Lauren Darcey's team broke the app into feature modules, switched to pure Kotlin with Anvil for dependency injection, moved to GraphQL, and rebuilt it with Compose and a modern tech stack.
The app dropped below 50MB for the first time in three years. Unit test coverage jumped from 5% to 70%. CI times fell to 30 minutes at p90 and stayed there.
