First, allow me to say how much I like ThumbJam, especially because of the quality of the sounds, and the creativity and musicianship that has gone into creating such an interesting iOS instrument.
But recently I've enjoyed ThumbJam even more than before, because of a new app we've been working on that plays the ThumbJam sounds over virtual midi... using a chord-playing interface.
Until now, I wasn't able to say anything about this, because the new app was in development, but it's now in the app store, so I thought I'd share with the ThumbJam community what happened.
Years ago, I started drawing "chord-progression maps" for young piano students. I was trying to make music theory, at least the songwriting aspects of it, a little more accessible to beginners. The maps developed over time, and were eventually shared at a website called Chordmaps.com... but the idea that you could touch a location on the map, and hear the sound associated with that particular chord, was still off in the future.
The exciting news is that now a variation of these music theory maps has been programmed as an app for iPhone (iOS version 5.1). It allows the user (even beginning musicians) to play power chords in any of 12 major keys by tapping just one finger at a time at specific locations on the screen. (Various options allow playing just the bass note, or just the chord notes, or even changing the power chord into a three-note chord that is either major or minor. These options can be easily changed while playing "live.")
During development, our "go to" sound source was ThumbJam, and I can tell you that this has changed my concept of what a songwriter can do on the iPhone/iPad/iPod Touch, and also my experience of what can be done with ThumbJam sounds when using them in a chordal context.
I'd like to invite and encourage members of the ThumbJam musical community, when you have a chance, to take a look at the website that describes the new app, and see if this chord-playing approach might be useful to you in your situation as a performer, writer, or educator.
The new app is called ChordMapMidi
The website with more information is http://mugglinworks.com/ChordMapMidi
I hope you find it as interesting as I have.