Firebase extensions

Hello all,
I think all users this great platform for create apps have a big big problem with monetisation, in-app purchase, or subscriptions for premium content.
I view new fitch from Google Firebase as EXTENSIONS (Firebase Extensions | Pre-packaged solutions that save you time).
One of them, is in-app purchase from service RevenueCat (https://www.revenuecat.com).

Because SAP Appgyver choose Firebase as basic tool, please search ASAP and give users your platform manual or tutorial how we can to use this extensions in our apps.