Sound greatI used one for hours yesterday browsing, a couple hours playing Lumines(a game that is said to kill phone batteries), Spotify running most of the time, an hour air playing to an Apple TV, an hour watching Youtube, twitter etc and this morning after another hour of Lumines I'm at 50 percent battery life. So I don't have exact numbers for you, but to me it's looking really really good.
wow! that's great battery life on the streaming video test.Battery is great comparing with ipad pro and air . https://www.cnet.com/products/apple-ipad-2017-9-7-inch/review/