MotionPhone is now available as an app for the iPad and iPhone. The app lets people create abstract animations together over a network, choosing colors, shapes, and forms that follow their fingers’ most subtle movements. By moving again-and-again in the same animated canvas, people can create layers and rhythms of abstract form and color, much like musicians layer track after track of audio in the studio sessions.

It was 1989 and I was roundly ignoring a verdant spring day in the HVAC hermitage of Brown University’s Computer Science Lab, when Henry Kaufman yanked me up from my workstation to say I must see Merce Cunningham’s dance company perform. Who’s that? I blurted to my friend as he pulled me out the lab’s card-keyed door.