Sign in with Apple (iOS App + Backend verification) API returns error “invalid_client”
问题 I'm trying to implement Sign In with Apple with an iOS app and a backend. The goal is this: The User signs in on the iOS app After a positive response the app calls an endpoint on the backend and hands over the authorizationCode The backend now needs to verify the authorizationCode with another call to apple's server. Here I'm confused. In order to make this call, the backend needs to provide a bunch of parameters: URL https://appleid.apple.com/auth/token Query Parameters client_id = com