There are a lot of reasons to leave a phone on during charge. Mine is on 24/7 with or without the charger attached. But... charging the phone faster is not one of the reasons. It will always take longer to charge a phone that is on verses off. May not be much of a difference, but the laws of physics say it has to be that wayI seem to get a better charge leaving the phone on. How many of you shut it off to charge it?