Hidden code found within Apple's newest iOS 7 beta (3) hints that the Cupertino company is looking to add new camera sensors in future products, most certainly the iPhone, which will be capable of recording 120 frames per second and super slow-motion video.
A developer, while surfing through code, discovered a new camera feature titled "Mogul" which boasts of the aforementioned features, confirmed after a few tests. 120fps video recording should allow for supremely stable and crisp videos, although the hardware should support it (both SoC and camera sensor). Such sensors do exist, and are made by the company Omnivision.
Apple has already let it be known that iOS 7 will allow for 60fps video capture, but 120fps will be a whole new level altogether. This new feature would also bring Apple's offerings up to par with the Samsung Galaxy S4, which already offers such a feature (120fps video and super slo-mo recording).