Consequences of enabling Low Power Mode
Low Power Mode restricts certain functions like background app refresh in order to conserve battery life. I thought I would list all of the restrictions I've found that Low Power Mode imposes, and others are of course free to add on if I missed any.
Background App Refresh is disabled
Mail will not fetch new mail automatically
Brightness is lowered (the max brightness is lower than with LPM off)
The battery percentage gauge cannot be turned off
Night Shift (iOS 9.3 and later) cannot be enabled
I read on one site that Live Photos will not animate in Low Power Mode, but I have been able to do so without issue so I don't think LPM impacts Live Photos at all.