Mapbox React Native
Installation
Installing packages for expo
npm install @rnmapbox/maps
Configuration
For iOS, Android and Expo there are different configurations you can find here Configurations Platforms
For expo:
Set RNMapboxMapsDownloadToken to your secret token. 
Add RNMapboxMapsDownloadToken to the @rnmapbox/maps config plugin in the plugs array of your app.
Then add you key in the the config.js/app.js
{
  "expo": {
    "plugins": [
      [
// highlight-start
        "@rnmapbox/maps",
        {
          "RNMapboxMapsDownloadToken": "sk.ey.."
        }
// highlight-end
      ]
    ]
  }
}
Rebuild app`
expo prebuild --clean
Configure permissions for location access
To show the location puck on the map with the LocationPuck component you use the expo-location plugin to configure the requires NSLocationWhenInUseUsageDescription property.
Install the plugin with npx expo install expo-location and add its config plugin to the plugins array
{
  "expo": {
    "plugins": [
// highlight-start
      [
        "expo-location",
        {
          "locationWhenInUsePermission": "Show current location on map."
        }
      ]
// highlight-end
    ]
  }
}
!!! In the App.js you use the public token or your secret token from mapbox and in the app.json file you use your download token. You can also set up your secret token in an env file