AG

Had the same problem with my iPad3 running on iOS 9. At times it would charge super fast, and at times it would charge only 2-3% overnight. At all times however the charging battery icon was displayed, so it was a case of fake charging. By chance a simple fix worked - I reversed the end of the charger which goes into the iPad port. Turns out for some reason one end of the charger when plugged in resulted in fake charging while the other end worked fine. I've now made a light mark on the side which works so I can plug it in with that side face up. Don't know the wiring technicality, but if you've tried all other fixes give it a try before going to Apple!