I've been working on this for a few months now. I took another pass at the vocals and guitars, and replaced the drum track with some free DrumsOnDemand acoustic drum loops, which I imported into GarageBand for iOS. The guitars and bass were done in AmpKit via Apogee Jam, keys and drums in GarageBand, vocals direct to MultiTrack via the Blue Yeti USB mic and the camera connection kit. All done on my iPad 2.

http://soundcloud.com/anorton/key-to-the-highway