Sorry guys, I don't usually post, but this thread is really starting to annoy me. Firstly it is impossible for the 920 to have better low light capabilities than the 1020, for the sensor is four times smaller, and thus it can only capture 1/4th of the light that the 1020 gathers. Furthermore, the argument that the 920 has a wider aperture than the 1020, hence contains superior low-light capabilities is a misguided one because sensor size and aperture are intrinsically linked. For example, because the 1020 has a smaller sensor than a full frame DSLR, its light gathering abilities is equivalent to a DSLR wit the aperture aperture is equivalent to approximately f8 or more. Moreover, despite the 720 having the largest aperture of F1.9, because of its minuscule sensor of one in three point two, to say that it has the best low light ability is ridiculous. The viewfinder, or even the image might be brighter on the 720 or the 920, but this has nothing to do with the phone's light capturing ability, rather it only demonstrates the phone's processing methods as well as the settings the camera captures in.
Basically, all I wanted to say is that the light gathering abilities depicted by aperture size is completely relative to the sensor size. Cheers