Whenever I Sign in with Apple for the first time on an Apple device, the screen stays white until closing the app and re-opening. This was flagged to me by the App Store review team, and noticed it happening in both apps.
It happens when signing in on a fresh app install as well as the appmysite previews (iOS).
We apologize for the inconvenience. Please create a ticket for this issue via the link - https://app.appmysite.com/email-support/ with screenshots or screen recording of the issue if possible and our support team will be more than happy to assist you in fixing the issue.