Exclusive seemed to sense A5's doubts, and their expression turned cold. "You're not going to back out on me now, are you?" they growled.
(combined with a USB Host Shield) is considered an "exclusive" or necessary feature for exploiting the (found in devices like the iPhone 4S and iPad 2).
Most people get this wrong. The Arduino runs at 5V, but USB runs at 3.3V.
