Here is a video about shooting with the Nokia Lumia 1020 with manual control in the Nokia Pro Camera app. Of course the camera works great if you just push the shutter button and let the automatic settings take over.
However, the Pro Cam app gives you increadible control of the image. You can manually set white balance, focus, iso, shutter speed (up to 4 seconds!), and exposure compensation. The adjustments all happen in real time on the back of the phone so you can see the results before you shoot. There is a gallery of images I shot with the phone on the National Geographic / Nokia hub.
Everything was shot with Pro Camera version 1.6 and I am certain that the software will get even better with later releases.