The tweaks include deprecating certain tools because of low adoption (including the Profile Expression Kit, Topic Search, Topic Insights and Topic Feed and Public Figure APIs) and limiting public content discovery APIs to Pages content and public posts on a select number of verified profiles. The company is also reintroducing search of Facebook Pages thanks to Pages API. As Facebook notes, though, "developers will need feature permissions to Page Public Content Access, which can only be obtained through the app review process."
The company is requiring anyone using Marketing API to manage and automate their advertising on Facebook to undergo an app review process; Lead Ads Retrieval and Live Video APIs will also require additional app review permissions. Finally, Facebook is allowing developers to run test queries through the Graph API Explorer App using their own access tokens.
Since the Cambridge Analytica scandal, Facebook has been scrambling to limit the data that app developers have access to. The company previously announced they were deprecating many APIs to limit the transfer of data outside of Facebook. This is just another step along the way, as the social network promises that yet more changes are on the way.