iPhone application publisher Chillingo (Zen Bound, Circuit Strike.One) today announced the development of Crystal, a free social gaming platform open to all App Store developers. Describing the service as "iPhone's answer to Microsoft's Xbox Live," Chillingo says that Crystal will allow players to create profiles, earn in-game achievements, and keep tabs on the gaming habits of friends. Crystal-equipped iPhone games will feature full integration with multiple social networking websites, enabling users to report their gaming progress on websites like Twitter and Facebook. Chillingo's platform will compete with a number of similar applications already available to iPhone developers, including ngmoco's Plus+ network and AGON Online. Crystal's software development kit will be available as a free download from Chillingo's website upon its release, and more information is available on the official Crystal SDK website.