I have an Android app with inapp subscriptions (with a 7 day free trial period) and I am trying to upgrade it to Google Play Inapp Billing v3 following these instructions:
https://github.com/android/play-billing-samples/tree/master/ClassyTaxiJava
I don't understand what is the purpose of the "Backend Server". What is it for ?
By the way, if you have any link to a detailed tutorial to deploy such a server (Google explanations given here are quite 'light'), I am interested :)
Thanks !