Designer Jorge Colombo makes art on his iPhone using the Brushes app and iSketch. His beautiful work – done on a phone! – features scenes of New York. Since his way of finger painting doesn’t actually immerse the hands in the fluid experience of finger paint, I think of it farther along the expressive therapies continuum, with more resistive media like acrylic and tempera paint or water color markers.
Read about his book at: http://www.chroniclebooks.com:6081/titles/new-york.html