Nokia Lumia 1520's phone-camera, man, that is one friggin' good camera. With this, image-quality-wise, there is practically NO compromise from a good compact camera to this one. Good colors, good contrast range, decent low-light performance, and a very sharp lens indeed.
(Of course there are other compromises, but not much. It has no zoom, and the autofocus is not as fast as the best compact cameras. And a big-sensor compact like Sony RX100 will do better in very low light.)
Note, I still use my iPhone 5S as my phone and main mini-tablet. It's only the screen size and the camera of the Lumia 1520 which beats the iPhone, the user experience is otherwise markedly inferior, in my opinion. (And the camera in the iPhone is probably next-best.)