In iOS 11, Apple has eliminated built-in Integration with Twitter, Facebook, Flickr, and Vimeo, a feature that allowed users to store their account information and access it within third-party apps that needed to use those services.
The Facebook, Twitter, Flickr, and Vimeo options have been ******* in the Settings app, and according to Axios, the four apps will **w be treated like other apps, using the iOS sharing extensions that were introduced back in 2014 with iOS 8.
iOS 10 left, iOS 11 right
Rather than continue to add support for different social services, Apple went with a different approach, adding sharing extensions with iOS 8 in 2014. Until **w, it has maintained the single sign-on for Twitter and Facebook in addition to supporting the sharing extensions for a wider range of apps.