If you are looking at this thread you might be having charging problems you just noticed after upgrading to 9.3.3 or even 9.3.2. A member named robnbill posted in this thread in post # 126 instructions that worked for me.
I created an account solely to post that that solution is a good one.
I have an iPad (4th with GSM) that was on iOS 9.3.1 with normal battery behavior. I'm not sure if I skipped 9.3.2 or did two upgrades in a short time, but after going to 9.3.3 I noticed my battery was draining rapidly. It was draining so rapidly I could watch it lose 1% every couple of minutes. Even when plugged in, charging could not keep up, but the drainage slowed to -1% every 7 minutes. When shutdown, charging seemed more normal, gaining 10% an hour or so.
Here is the list of things I tried to stop the bleeding, all of which seemed to make no difference. Note that there were dozens of reboots occurring, including at least one between each step.
List of things that did NOT help:
- Downgrade to 9.3.2 (I tried to downgrade to 9.3.1, but my "device is not authorized" to do so, apparently)
- Delete Facebook (suggested in many related threads)
- Delete other "hungry" apps suggested in this and other threads
- Sign completely out of iCloud (on the problem iPad only)
I had to keep the iPad powered down most of the time for a couple of days to keep it from going to zero.
Luckily, I stumbled across robnbill's post #126.
We have 3 Macs, 3 iPads (including the "bad" one), 2 iPhones, and 1 Watch in our Apple account, of which only the one 4th Gen iPad had the charging problem. We powered them all down as suggested by robnbill. Then powered them back on 1 by 1. And so far, so good. The iPad with the battery issues is now charging fine. I'll reply to this again if something goes wrong, but ...
Thank you robnbill for your research into this! Solved it for me.