Mark Gurman over at 9TO5Mac is reporting that Apple is sending out iPhone 4S models to a few select developers, however, it is unclear if this is a new phone or just a slightly revised iPhone 4 utilising the iPad 2s A5 processor. The article mentions information found in the iOS 4 SDK which contains code to support the A5 and reports that the operating system found on this prototype is a "version of iOS 4 that supports the next-generation hardware."
One of the reasons for Apple to use the A5 over the A4 is the level of gaming functionality. It is reported to be over nine times the capacity as seen in the iPad 2 and surpasses many other competing devices. Additionally 9TO5Mac has heard that "Apple is going to push this gaming performance and speed as one of the next-generation iPhone’s major marketing points."
It is already known that the iPhone 5 will feature this technology but this latest news, which comes from person named "iPhone 4S", makes us question whether or not Apple may be considering releasing a 4S model of their popular iPhone series. These prototypes may just be a models for developers to help them get ready for the new phone, which Neowin reported might be available in September.