In my harsh battery test, where I play videos back to back with the screen set at 75% and the Wi-Fi on to collect email, the iPad mini exceeded Apple's battery life claim of 10 hours and lasted 10 hours and 27 minutes.

WSJ: Sizing Up the New iPad Mini

In my harsh tablet battery test, where I play a constant loop of video with the screen set to 75 % brightness and Wi-Fi on to retrieve email in the background, I got almost exactly five hours, which is Asus's official battery life estimate.

WSJ: A PC and Tablet 'Brick' for the Price of One