Mine has only rarely lasted more than 6 hours between charges. I got it to do 9.5 hours once, basically by not using it much, but then what's the point?
With the mophie juice pack air, I can last all day if I'm fully charged by the time I wake up in the morning.
Games often, Flipboard and twitter quite a bit, email and slack and chat and whatnot almost constantly, so I'm doomed to not be able to last all day without some help.
Quite frankly, with how fast this thing is, and the kinds of graphics it can push, I'm shocked it lasts more than 2 hours.