App researcher Jane Manchun Wong has discovered that Twitter is trying to let you sign into the app with your Apple ID. An evidence Wong has included a new "Connected accounts" option with Apple listed as a signing-in option. Twitter explains, "These are the social accounts you connected to your Twitter account to log in. You can disable access here."
Apple does offer this option to apps and sites, but it isn't a requirement. To use Sign in with Apple, you need to use two-factor authentication and be signed in to iCloud with that Apple ID on your device. Twitter has been using its own sign-in systems so far, but perhaps that might change in the future.
Via: 9to5Mac