The QX cameras are housed within a lens like body which can be controlled and attached to your smartphone via a special case (Xperia Z1 / Z2) or an adjustable clamp (all other smartphones). It uses a much larger sensor and better optics than the best of the current smartphone camera crop. It isn't without its faults though, the lack flash and inconsistent performance between the camera and controlling smartphone are good examples.
Leaks which appeared at the Unofficial Xperia Blog and Sony Alpha Rumours sites point to a revised QX camera which incorporates a better sensor, a pop-up flash, performance improvements and support for Sony's E-mount lenses, making the setup equivalent of one of Sony's Alpha cameras in a more pocketable form.
I've always liked the concept of the QX camera, especially the ability to separate the camera from the viewfinder for things like wildlife shots, it sounds like Sony now have a product that might be worth pursuing.