Member-only story
Guide To Make Your React Native App Fast
Not a Medium Member? “Read For Free”
People pick React Native because they want an app that feels like a real native app, not a website inside a box. The goal is smooth movement at 60 frames per second (FPS). Most of the time React Native handles speed for you. But sometimes it can’t, and you need to step in and help.
In this article, I will explain how React Native draws your screen, why an app starts to lag, and the most common mistakes that slow things down, with easy fixes for each one.
First, understand frames
A video is just many still pictures shown very fast. Each picture is called a frame. The more frames you see each second, the smoother the motion looks.
Phones show at least 60 frames every second. That means your app has only 16.67 milliseconds to prepare each frame. If the work takes longer, the frame is skipped. This is called a dropped frame, and the user sees a stutter or feels the app is stuck.
So performance work in React Native comes down to one rule: keep every frame’s work under 16.67ms.
Two threads, two frame rates
Open the Dev Menu in your app and turn on “Show Perf Monitor”. You will see two frame rates, because your…
