Loopy, the sophisticated, tactile live looper app that reinvents iPhone and iPad music making. Layer up to 12 loops with overdub, stereo, count-in, variable tempo, import/export, and full MIDI clock and control support.
Source: loopyapp.com
Having heard the Melbourne based developer of the Loopy app interviewed on local 774 radio https://soundcloud.com/774-abc-melbourne/loopy-the-tonight-show-performance  and checking the YouTube link from the Jimmy Fallon Show featuring Billy Joel and the Loopy App, (and especially as the HD iPad app is on sale for half price), I just had to grab a copy. After a quick play I can see that I am going to be “wasting” a lot of time “going loopy”. This is a must have app for anyone musically inclined and I can see it really taking off in classrooms.
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Will be interesting to see how it compares to something like Launchpad. I think I might waste a lot of time with this if I am not careful.