I inherited an iPad and a few days ago started looking at apps for recording, drum beats, GarageBand etc. Then I stumbled on TrueFire's 50 must know blues licks which is a great value at $10.00. I highly recommend the app which includes video lessons and tab in a well designed easy-to-follow interface. I've got the iPad connected to a firewire interface that pushes audio out to a pair of monitors and the sound quality is great.
Check it out here, along with other lesson packages: http://truefire.com/blues-guitar-lesson ... tar-licks/