What I think is odd is that even if you turn the iPAD off, by doing the following:
- Begin by locating the iPad's on/off/sleep button. This button is on the top right-hand corner of most iPad models
- Press the hold button for a few seconds, until a slider appears at the top of the screen that says Slide to power off.
And before that, reducing screen brightness to 0%, airplane mode on, the rest of apps closed, etc. the battery still drains a little after a few days/week(s).
My iPAD 4, bought in 2013, had a 29/30% battery degradation, according to this app:
https://itunes.apple.com/br/app/battery-life-check-internal/id1080930585?mt=8
When I turned it on again after a week, the battery % was reduced from a full/100% charge to 93. I had the idea to drain the battery to 0% and charging to 50% (since I am selling this thing and will need to store for a long time without using again), and then I noticed the iPAD's temperature changed from 35ºC/95ºF to 40ºC/104ºF once I increased the screen brightness to 100%.
I have no idea if it was 30% before that, all I know is that now is 35% and even with all settings turned off or reduced, it remains that way. Now that is charged to 50%, I have turned it off again. It is said that the rise of temperature can be detrimental to the health of the iPAD battery, I just hope this didn't happen even more only because of this change in the brightness I did.
At least here where I live, not only the battery can't be replaced (and from what I heard, Apple doesn't do that, perhaps it's not worth the hassle for them), and after more than 1 year since the purchase date, the only alternative is to buy a new iPAD.
As for the IPP 9.7, it seems that after a few days, even with airplane mode on, you lose 2, 3%, then again in this case I didn't turn it off.