I have to build an app for iOS and Android and I was thinking about using React Native to do the job, but I don't find anything regarding In-App Purchase. Do you know any existing solution for adding In-App Purchase to both the iOS and Android version without too much headache?
I am the author of an InApp Billing library for RN on Android; react-native-billing.
I've been considering also supporting iOS from the same library, but it would require a substantial rewrite since there is some difference in feature-parity. Also the API behaves in different ways.
For now, if you need iOS support as well, I'd use react-native-in-app-utils.