public void DidComplete(ASAuthorizationController controller, ASAuthorization authorization) { var credential = authorization.GetCredential <ASAuthorizationAppleIdCredential>(); if (credential != null && !string.IsNullOrEmpty(currentNonce)) { appleToken = credential.IdentityToken.ToString(); var firebaseCredential = OAuthProvider.GetCredentialWithRawNonce("apple.com", credential.IdentityToken.ToString(), currentNonce); Auth.DefaultInstance.SignInWithCredential(firebaseCredential, SignInOnCompletion); } else { appleToken = string.Empty; SetVerificationStatus(VerificationStatus.Failed, "Sign in failed"); } }