[porsupah]

Well, it depends how you use the available space. With a simple stack of sensor and lens pointing out of the phone, there's very little height available. But if you were to arrange the optics down the length/width of the phone, you'd grant yourself rather more space. This patent talks of external add-ons, but the same principle would be applicable internally:

http://appleinsider.com/articles/14/01/28/apple-granted-two-...

And then there's the option of having multiple cameras taking the same shot, with different focal lengths (whether fixed or zoom) on each. You're still limited in dynamic range by the photosite size, but as we're seeing now, that's often not so huge a problem in many scenarios. One startup working on such a principle is Light:

http://www.imaging-resource.com/news/2015/04/18/photo-startu...