Here a nexus 7 2nd vs ipad mini review
http://www.gizmag.com/ipad-mini-vs-nexus-7-2013/28450/
They say battery should be about 10 hours but it last way longer on mine. I can work 2 night shift of 10 hours without charging it. I use it to read manga and comic most the time and watch 1 movie by night.