Learn how to create a new Expo project and run it on your device.
Before creating a new Expo app, you have to make sure that:
If you need help making these tools work on your end, go back to the Installation before proceeding.
To initialize a new project, use
# Create a project named my-app
npx create-expo-app my-app
# Navigate to the project directory
You can also use the
--templateoption with the
npx create-expo-app --templateto see the list of available templates.
Start the development server by running the following command:
npx expo start
When you run
npx expo start (or
To open the app:
You can open the project on multiple devices simultaneously. Go ahead and try it on both phones at the same time if you have them handy.
First, make sure you are on the same Wi-Fi network on your computer and your device.
If it still doesn't work, it may be due to the router configuration — this is common for public networks. You can work around this by choosing the "Tunnel" connection type when starting the development server, then scanning the QR code again.
npx expo start --tunnel
Using the "Tunnel" connection type will make app reloads considerably slower than on "LAN" or "Local", so it's best to avoid tunnel when possible. You may want to install a simulator/emulator to speed up development if "Tunnel" is required for accessing your machine from another device on your network.
If you are using a simulator or emulator, you may find the following Expo CLI keyboard shortcuts to be useful to open the app on any of the following platforms:
Open App.js file in your code editor and change the text to "Hello, world!". You are going to see it update on your device. This is great progress! You now have the Expo toolchain running on your machine, can edit the source code for a project, and see the changes live on your device.
Expo Go is configured by default to automatically reload the app whenever a file is changed, but let's make sure to go over the steps to enable it in case somehow things aren't working.
Make sure you have the development mode enabled in Expo CLI.
Close the Expo app and reopen it.
Once the app is open again, shake your device to reveal the developer menu. If you are using an emulator, press Ctrl + m for Android or Cmd ⌘ + d for iOS.
If you see
Enable Fast Refresh, press it. If you see
Disable Fast Refresh, dismiss the developer menu. Now try making another change.
Let's face it. You are going to make mistakes and typos and you are going to get warnings and errors in your app. So let's learn a little bit about how to read and interpret errors.