The Pages, Events and Groups APIs, as well as Facebook Login, will all require developers to submit their app review. What's more, Facebook is deprecating a significant number of fields associated with these. For instance, developers using Facebook Login will not be able to access information about users' relationship status, religion, education and work, among other fields. These fields have also been removed from Facebook's User node.
The Events API will no longer provide access to content such as posts, comments, photos and videos, as well as information about who is and isn't planning to attend events. The Pages API will now require a Page Access token for specific endpoints and no longer returns social context elements.
Facebook has completely deprecated its Search API for pages, groups, events and users, and removed information about age, gender and country from the app_event metric in its App Insights API.
All of these changes follow those the company made without warning to the Instagram API. According to comments on Hacker News, "although their blog posts say they are only removing select endpoints, [Facebook has] basically shut off access to core endpoints well beyond what they listed," suggesting that Facebook's developer platform, as it had existed, is effectively dead.
While it is understandable that Facebook felt the need to take drastic action to protect its core business, the company's developer ecosystem has been one of the largest and most active, and these changes would seem to put the viability of that ecosystem in jeopardy going forward.