3rd party logins have the advantage that sharing content from within your app on those social platforms becomes less of a friction unfortunately - if that's wha

3rd party logins have the advantage that sharing content from within your app on those social platforms becomes less of a friction unfortunately - if that's what your app relies on. Email-only logins work fine with technical users, but non-technical ones absolutely suck at maintaining their logins and passwords. You lose users because they can't login for whatever stupid reason - one of the thousand stupid reasons - and they turn away to never come back, or they register afresh. This is the reality and yes, 3rd party auth is beneficial for popular (non-techie) services. As for Apple Sign-in, haven't tried it on the development side yet but I can imagine it reduces friction even further and makes the user experience even nicer. This may be such a big bonus for your service that you may ignore the fact that you can't always collect your users' real email addersses. Find other ways to communicate: in-app messaging for example. If the user deletes your app then retargeting via email won't help much anyway - they will mark you as spam and overall it will probably do more harm than good, I think.