I messed about with comics, tested some short hd clips and transferred files back and forth and without realising it i think I got a good 4 or 5 hours out of it and it still says 35% left. I've got the screen brightness set to 25% and I think i had it set to that in ACV too, (was trying 2 versions of acv, one worked in adjusting the brightness and one didn't)If it keeps up with that kind of battery life while reading then i'm pretty happy with it overall.videos tests were weird, it played 720 well but not enough to watch a film, just enough stuttering for it to be a pain. 1080 was actually the same but for some reason the audio didn't work.