Important: For Android, in AndroidManifest.xml add your TomTom API key
<meta-data android:name="OnlineMaps.Key" android:value="YOUR_MAPS_KEY" />
For IOS, in info.plist, add it as below or use Xcode for ease of use.
<key>OnlineMap.Key</key>
<string>YOUR_MAP_KEY</string>
I have prepared a tutorial for this repository if you want to check out.
Part.1 - Android: https://cuneyt.aliustaoglu.biz/en/using-tomtom-maps-in-react-native-with-android/
Part.2 - IOS: https://cuneyt.aliustaoglu.biz/en/using-tomtom-maps-in-react-native-part-2-ios/