Apple has revoked Facebook s enterprise iOS developer certificate on the heels of a Facebook Research VPN app that was being distributed to consumers. The app paid teens and Millennial users up to $20 a month to install the app, referred to as Project Atlas, on iOS or Android. Apple has strict data-collection policies as part of its developer policies, which bar the collection of data about usage of other apps or data that is not necessary for an app to function.
Source: https://threatpost.com/apple-blasts-facebook-over-data-sucking-research-app/141311/

