There are two tools that you need to develop apps with Expo - a desktop development tool and a mobile client to open your app.
Desktop Development Tool: XDE
XDE stands for Expo Development Environment. It is a standalone desktop app that includes all dependencies you’ll need to get started.
On Linux, open with
chmod a+x xde*.AppImage and
Mobile Client: Expo for iOS and Android
The Expo client is like a browser for apps built with Expo. When you boot up XDE on your project it generates a unique development URL for you, and you can access that from the Expo client on iOS or Android, either on a real device or in a simulator.
On your device
Required Android and iOS versions: The minimum Android version Expo supports is Android 4.4 and the minimum iOS version is iOS 9.0.
You don’t need to manually install the Expo client on your emulator/simulator, because XDE will do that automatically. See the next sections of this guide.
Install Xcode through the Apple App Store. It’ll take a while, go have a nap. Next, open up Xcode, go to preferences and click the Components tab, install a simulator from the list.
Once the simulator is open and you have a project open in XDE, you can press Open on iOS simulator in XDE and it will install the Expo client to the emulator and open up your app inside of it.
Download Genymotion (free version) and follow the Genymotion installation guide. Once you’ve installed Genymotion, create a virtual device - we recommend a Nexus 5, the Android version is up to you. Start up the virtual device when it’s ready.
Once the emulator is open and you have a project open in XDE, you can press Open project in Expo on Android in XDE and it will install the Expo client to the emulator and open up your app inside of it. If you run into any issues follow our Genymotion guide.
To get started with Expo you don’t necessarily need to have Node.js installed, but as soon as you start actually building something you’ll want to have it. Download the latest version of Node.js.
Some macOS users encounter issues if they do not have this installed on their machine, so we recommend that you install Watchman. Watchman watches files and records when they change, then triggers actions in response to this, and it’s used internally by React Native. Download and install Watchman.