Leaked photos of Apple’s upcoming iPhone 5S reveal a larger-capacity battery and a new dual-LED flash system for the rear camera. These photos also indicate that the next-generation iPhone will feature an A7 chip instead of a modified A6 chip, like the A6X found in the fourth-generation iPad.
From Mac Rumors:
As seen in one photo, the chip carries an Apple model number of APL0698, suggesting that this is indeed intended to be branded as an A7 chip rather than a modification on the A6 chip found in the iPhone 5. The original A6 chip carried a model number of APL0598, with the A6X found in the fourth-generation iPad carrying an APL5598 model number, demonstrating how Apple varies the first digit for members of a given A-series family and increments the second digit when transitioning to a new family.