The past four weeks have been an active one for Web and mobile app developers - particuarly for those in any way using Facebook's API's.
Facebook has updated four of its API's in the last month: the Social Graph API and the Real-time Updates API were updated December 20th, and the Facebook Chat API and the Social Plugins were updated in the past week.
While changes to the API's themselves were routine and actually quite minor, 500 million users worldwide (some say closer to 600 million) demand attention.
Let's take a closer looks at those API's recently updated:
Graph API: Perhaps the most important API from Facebook, the Graph API gives developers the opportunity to view connections within a particular social graph. Thanks to every object in the social graph having a unique ID, developers can display Facebook wall content, pages and even apps within their own websites and applications (with minimal resources). A good example of the possibilities is the FB.WALL jQuery plugin featured at WM in early January.
Real-time Updates API: The Facebook Real-Time Updates API allows developers to create applications that respond to real-time data updates from Facebook subscriptions. Objects that can be subscribed to are: user, permissions, page. Uses REST protocol and JSON data format.
Facebook Chat API: This API allows users to integrate Facebook Chat into their Web-based, desktop, or mobile instant messaging products. The user's instant messaging client connects to Facebook Chat via the Jabber/XMPP service. Uses XMPP protocols and responses are formatted as XML or vCard.