As a Post-NAMM celebration, the folks at Rock Prodigy are giving away their app as a free download all week. Check it out on the App Store here.
The app's description on its official website reads: "Rock Prodigy is your mobile instructor that works with any real guitar. Use it to learn guitar and songs faster than ever. Follow the Rock Prodigy lesson plan to take you from beginner to pro. Rock Prodigy listens to your guitar, shows you what to play, and gives you points for hitting the right notes."
You can head here for more info on the app.