$m@Rt@$$
Expert Member
My 5s used to lose 2-3% overnight on standby, since I installed iOS 10 I'm seeing around 20% loss on overnight standby. It's a spare device and doesn't have many apps on that could be the cause, nothing else has changed since the update.
That's one reason my 6s is still on iOS 9.
I've also found active usage doesn't make any difference on my iPad. But standby has dropped quite a bit.