Chillingo recently announced that it would be launching Crystal SDK, a service joining the increasingly crowded social network market for iPhone games. Xbox Live on the Xbox is an official social network, but the iPhone has no such official service. A crowd of contenders, from the popular OpenFeint service to ngmoco's Plus+ network, are jumping in and trying to get developers on board with them. Crystal SDK is one of those -- they've now launched the official website and are asking developers interested to sign up and see what their software has to offer.
Like many of the other services, Crystal is offering to integrate challenges, achievements, leaderboards, and other social services into iPhone apps. The SDK seems like it's still pre-release, however -- there's only a signup, no information on cost or implementation or anything else on the site. Still, if you happen to be an iPhone developer still looking for a network to hook up with, they might be the one for you.