This is a post that has been a long time in coming. Quite a few months ago, two manufacturers sent me keyboard controllers that are compatible with iOS devices, Macs and PCs, but it's taken me until now to get these two devices tested. The Line 6 Mobile Keys 49 (US$199.99 MSRP) and Samson Carbon 49 (US$89.99) are both 49-key keyboard controllers that are useful with music apps like Garage Band.
Both are USB powered, so you don't need to plug in any sort of AC power brick or use a stack of batteries. I was surprised at how little current draw the keyboards seemed to have, as using each for an hour or two with Garage Band on the iPad didn't seem to have much of an im
