Apple was set to release the iPhone 5 in 2011, but Steve Jobs pushed back the release after reports of poor battery life. It's also thought that the late Apple co-founder felt the larger screen size would have fragmented the iPhone community.
BusinessInsider reports that one of its sources had a brief play with an iPhone 5 prototype a few months before the iPhone 4S was announced - and despite the early stage of its development, it brought quite a few changes to the table.
The source stated that the new handset was built from a prototype material at the time, but was intended to have an aluminium back like the iPad 2 when manufactured for real. It also came with a 4in screen, making it half an inch larger diagonally than the current generation of iPhones.
Another obvious change was the replacement of the traditional home button with a touch interface, like the screen. Holding down this button would reboot the device. The source also mentioned that Apple planned to use a "liquid metal" technology to allow for not only multiple colour options, but to also add aesthetic damage resistance, as a scratch wouldn't remove colour.
The final bits of information about the prototype were that it included a 10-megapixel camera, that the voice search application Siri was named 'Assistant' - and that battery life was poor. This last factor is said to be one of the main reasons it is claimed that Steve Jobs pushed back the release of the handset, using the 4S as a stopgap to give Apple more development time.
Battery life issues on an iPhone. Who'd a thunk it?