My Facebook app used to work on iOS, Android and Web.
I have some Facebook permissions that were already approved for my app, and I want to remove Android and iOS platform (since I don't user them anymore).
Lets say that publish_actions permission was approved for my app when I had all the platforms. If I remove and re-add the platform in the future, will I still need to go through the Facebook Review process ?
Does the permissions are approved based on the platform or based on the app ?
No, if you remove a platform you don't need and later re-add it, or add a new platform, that will not require you to re-submit your app for review (unless your app on the new platform also requires new permissions you haven't already been approved for). We may still review apps from time to time to ensure compliance with our policies, but it would not be automatically triggered by adding a new platform.