React Native Performance: JavaScript Thread 🧠 vs UI Thread 🎨 Explained

React Native apps run on multiple threads, but the two most important are the JavaScript thread and the UI (main) thread. In this video, we’ll break down how they work, what causes them to slow down, and how to optimize your app’s performance. 🚀 🔑 What You’ll Learn 🧠 JavaScript thread responsibilities (state, logic, events, navigation) 🎨 UI thread responsibilities (rendering, gestures, animations) 🚨 Common performance blockers for both threads 🔍 How to detect issues with Flipper, Xcode, and Android Studio ⚡ Optimization strategies for JS and UI threads 🚀 How the new architecture (Fabric & TurboModules) improves performance 🧪 Real-world code examples of bad vs good practices Perfect for React Native developers who want to avoid app freezes, improve FPS, and deliver smooth animations. ⏱ Chapters 0:00 – Intro 0:40 – What are Threads in React Native 2:00 – JavaScript Thread Responsibilities 3:30 – Common JS Thread Blockers 5:10 – UI Thread Responsibilities 6:30 – Common UI Thread Blockers 8:00 – The Bridge & Bottlenecks 9:20 – Detecting Performance Issues 11:10 – Optimizing the JavaScript Thread 13:20 – Optimizing the UI Thread 15:00 – New Architecture (Fabric & TurboModules) 16:20 – Real-World Example (Bad vs Good) 17:40 – Summary & Final Tips 📚 Resources & Links 📌 React Native Playlist → https://youtube.com/playlist?list=PLEnLIMmMxb5oA7rEnHtQ6lS-v-NQ4lJjK 📌 GitHub Repo (Source Code + Notes) → https://github.com/coding4dev 📌 Coding 4 Dev Website → https://coding4dev.boadtechnologies.com 🔗 Follow Coding4Dev on Social Media: Instagram → https://instagram.com/coding_4_dev X (Twitter) → https://x.com/Coding4Devs GitHub → https://github.com/coding4dev LinkedIn → https://linkedin.com/company/coding-4-devs 🏷 SEO Tags react native performance, react native js thread vs ui thread, react native optimization, react native performance bottlenecks, react native ui freezes, react native fps, react native new architecture, fabric turbomodules react native, coding4dev react native 🔥 Hashtags #ReactNative #Performance #JavaScriptThread #UIThread #MobileDev #Coding4Dev #SmoothApps