The 620?s camera isn?t the best anyway, so Nokia Camera is quite useless. Changing Focus and everything has not as much impact (or none) as in the proper PureView devices.
I can shoot very good pics with stock camer app (which will be improved with WP8.1). Nokia Camera is too slow and doesnt give me much advantage.
Nokia camera beta has been updated more recently than Nokia camera, takes good pics too but the problem is that you cannot delete pictures in the app without try to reframe first.