After Music Sales released their 'Killer Riffs' and 'Freestyle' App which both hit the iTunes Music App Top Ten Charts, They have released 2 new apps you may want to check out.
Scale Cards is an app that is designed to teach you how to play over 50 essential guitar scales. You can view each scale on a guitar neck diagram, guitar tablature or on a video clip.
Chord Cards is an app that has the same features at the scale cards. 25 of the chords are movable shapes so they can apply to other areas of the fretboard giving hundreds of chords to learn.
Each app is $1.99. You can check out the apps at the Music sales apple store