Been using Nokia's for a while. Longer exposure times (and great manual controls in general) are a godsend. My 928 is spooky good in low light. The 929/930 isn't as good actually. I would say look at the smartcam.club for some comparisons between smartphone cameras but it's down right now. The oversampling that the higher res models do helps squeeze more (quality) out as well.
The Lumia 1020 is still quite viable, old Pureview 808 is quite remarkable still, as is the new Panasonic DMC-CM1 (Android). All have massive sensors.
Looks like the camera app ProShot should be out on Android soon (though I suspect compatibility could be a pain), already out on WP and iOS. One cross platform camera app with full manual controls to rule them all.