We?ve updated the App Store Review Guidelines to provide criteria for when apps are required to use Sign in with Apple. Starting today, new apps submitted to the App Store must follow these guidelines. Existing apps and app updates must follow them by April 2020.
Developer.Apple.com
Fantastical 3 ? als neue App ? war bereits verpflichtet ?Sign in with Apple? anzubieten. Alle existierenden App-Store-Apps sind ab April dran. Ich wette, dann bekommen wir mehr Zahlen wie populär diese Anmeldeoption tatsächlich ist.

Mezzanine lets users sign using their Apple, Facebook, or Google accounts, or by creating an account with their email address. [?] Of the 232 users that joined Mezzanine in the first couple of days, these were the preferred sign in methods: Apple (42%), Email (41%), Facebook (9%) und Google (8%). Ben Packard
Eine Motivation für Entwickler, die ich bislang noch nicht auf dem Schirm hatte, erwähnte Pedro Marques:

Apple ID?s are tied to hardware, making it impossible or at best highly impractical to create a large number of fake accounts. If an app were to use Sign In With Apple exclusively, they would largely eliminate fake users from their platform. Imagine Twitter without fake accounts.
? Pedro Marques (@MetroManTO) January 28, 2020

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