There is a 24 percent reduction in battery capacity to get the iPad slimmer, but Apple says it's able to keep battery life the same at about 10 hours for Wi-Fi Web surfing. That's because the A7 is more efficient at using power. In my tests, I actually got more out of the Air: 14 hours of iTunes video, compared with 12 hours on last fall's model.
I was disappointed, though, that the Air doesn't go even further. I would have wanted to see a fingerprint sensor for unlocking the device, similar to what's in the iPhone 5S. The Air also doesn't have the 5S's improved rear camera or the various 5S camera features that take advantage of the speedy A7 chip. That includes the ability to shoot slow-motion video and take up to 10 photos per second. (That said, I make fun of people who take pictures with iPads and block my view.)