Setup

• Create your application client on https://auth0.com/
• In the application settings you need to add the AuthSession docs callback url, which looks something like this: https://auth.expo.io/@your-username/your-app-slug. In the app code we have https://auth.expo.io/@8base/react-native-example because we are signed in as @8base and the slug for this app is react-native-example. You will need to replace 8base with your Expo username.
• Find references to https://brentvatne.auth0.com/authorize in App.js and replace it with the authorization endpoint for your Auth0 account, which you can see on your Auth0 dashboard.