How to start 'metro' (React Native)

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Good question 👍
The Metro bundler is the JavaScript packager that React Native uses. It must be running in the background for your app to load JS code.

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🚀 How to start Metro bundler

1. Go to your React Native project root (where package.json is).

   bash
   cd ~/Desktop/your_project_name
   

2. Start Metro:

   bash
   npx react-native start
   

   • By default, Metro will run on port 8081.

   • Leave this terminal window open.

3. In another terminal, build & install the app:

   bash
   npx react-native run-android
   

   or

   bash
   npx react-native run-ios
   

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🌐 For wireless debugging

If you’re not using USB, run Metro with your laptop’s IP address:

bash
npx react-native start --host <your-laptop-ip>

Then configure your phone (Dev Settings → Debug server host & port) with:

makefile
<your-laptop-ip>:8081

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⚡ Pro tip: If you already ran npx react-native run-android, Metro usually auto-starts in another tab. But if you closed it, just re-run npx react-native start.

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Do you want me to also show you how to make Metro auto-restart whenever you run run-android, so you don’t have to open it manually each time?