Setup with Expo (Run on Your Phone)
Expo is the easiest way to start — create an app and see it live on your own phone in minutes.
What you will learn
- Create a new app with Expo
- Start the dev server
- Open the app on your phone with Expo Go
Why Expo
Expo is a free toolkit that removes the painful setup. You do not need Android Studio or Xcode to begin. You create a project, run one command, and open the app on your real phone through a free app called Expo Go.
Create and start a project
You need Node.js installed (the same Node you used for React). Then create the app and start it:
# create a new app (pick a name)
npx create-expo-app@latest mynotes
cd mynotes
npx expo start
# a QR code appears in your terminalNote: Output: Metro waiting on exp://192.168.1.5:8081 Scan the QR code above with Expo Go (Android) or the Camera app (iOS). The dev server (called Metro) is now running and waiting for a phone to connect.
See it on your phone
- Install Expo Go from the Play Store (Android) or App Store (iOS).
- Make sure your phone and computer are on the same Wi-Fi.
- Scan the QR code: Android uses the Expo Go app, iOS uses the Camera app.
- Your app opens on the phone. Edit a file, save, and it reloads instantly.
Tip: That instant reload is called Fast Refresh. Change some text in App.js, hit save, and the phone updates in about a second — no rebuilding.
Watch out: If the app will not load, the cause is almost always the network: phone and computer must be on the same Wi-Fi, and some office or college networks block the connection. A phone hotspot usually fixes it.
Q. What is the main reason beginners start with Expo?
✍️ Practice
- Create an Expo app and open it on your phone with Expo Go.
- Change the welcome text in
App.js, save, and watch it reload on the phone.
🏠 Homework
- Get the starter app running on your phone and write down each step you took, so you can do it again from memory.