— The Air shares the A7 processing chip found in the new iPhone 5S. Apple says it's twice as fast as last fall's model. The Air also comes with a companion M7 processor, which improves battery life for motion-related sensor data. The A7 processor uses a 64-bit system similar to desktops, which is mumbo-jumbo for saying that it handles large amounts of data more efficiently. This makes the Air great for games and other data-intensive apps once they are adapted to take advantage of the new chip. Only a few are right now.
— Two Wi-Fi antennas work to deliver up to twice the speed. I downloaded the pilot episode of the "Pretty Little Liars" spinoff "Ravenswood" in less than 20 minutes. It took last fall's model 39 minutes to do the same.
— The Air adds a microphone on the back, while keeping the one on top. When recording video in a noisy room, I get better sound from the subjects and less ambient noise. There's a second stereo grill, too, for better sound balance when held vertically, though sound still comes from one side in horizontal mode.
— Cellular versions, offered for $130 more, work with a greater number of 4G LTE frequency bands. There's now a universal model, rather than two different ones before. That means you can switch U.S. carriers and use it around the world more easily.
