I have been using Tristan Zand's iOS app Loopr a bit via my iPad.
I did this piece recently using my recently de-fretted mandolin.
I did 4 foundation trax in Loopr, exported them, important in to Audacity, extended and manip'd some using PaulStretch and some reversal. Piece was done for this weekends Sound-In.org event.
- 'Acoustic guitar renaissance, color blue, repetitive minimalism'