React Native Blog Mar 28, 2016

Dive Into React Native Performance

Article Summary

The React Native team made their app startup twice as fast. Here's how they tackled one of mobile's most critical performance challenges.

Facebook's React Native team shares their journey optimizing performance across iOS and Android, with a particular focus on app startup time. This post dives into why performance matters especially in emerging markets with 2011-class phones on 2G networks.

Key Takeaways

Critical Insight

Facebook doubled React Native startup speed by treating performance as the difference between usable and unusable apps in emerging markets.

The full article on Facebook Code reveals the specific technical approaches they used to achieve these dramatic improvements.

About This Article

Problem

React Native apps were slow to start up, which made a bad first impression. This was especially problematic for users on older phones with 2G connections in emerging markets, where performance directly affected whether people could actually use the app.

Solution

Facebook's React Native team worked through the framework's performance issues systematically. They profiled the code to find bottlenecks in list view scrolling, memory use, and UI responsiveness, then fixed them.

Impact

Startup speed improved by 2x. Apps that felt sluggish became responsive, and devices with limited resources could finally run apps that were previously too slow to use.