David's interest in music led him to build FlexiGesture, a musical instrument that learns the player, rather than the player learning the instrument. His other research interests include designing ubiquitous/pervasive systems and interfaces for expressive gestural media manipulation. His work was on a project called Siftables, a collection of small, wirelessly networked devices that can physically embody and display pieces of media, as well as sense how they are being manipulated.