Chordbot

This is Chordbot.
In my humble opinion the most useful music app I own. Why? Because I like building songs from a chord structure and once I have those chords in place I like to build the rest of the track from there. There are other apps that let me put chords together but I then have to sequence them to hear what I've got. If it's wrong I then have to change the incorrect chords an re-sequence and that's time consuming and annoying.
Chordbot gets rid of that sequencing stage. You choose the chords, tell Chordbot how many times you want that chord to play then hit play and off it goes in an endless loop. You can change chords on the fly which makes previewing a track really easy and quick.
Not only that but Chordbot adds a style of your choice to your arrangement so you can get a feel for how your finished track will sound. While the styles don't cover every style you can easily find something suitable.
For song building or rehearsal it's an extremely useful tool.
If that wasn't enough you can export MIDI and Wav files through iTunes but an email export is on the way very soon. Another addition to Chordbot in the next update will be Audio Copy so your instant backing track can be added to other apps!
Grab a copy, it's getting better all the time.