You can read the full history in this story by my college band friend Peter Landers, but the short version it that is was discovered by a Kyoto University pharmacologist in the mid-1990s who was searching for better transplant drugs.
Designed by the same team as the full-fat version, aspiring DJs can enjoy two waveform-based decks, with three-band EQ, eight effects (ported over from Trakor Pro) all redesigned from the ground up for the iPad's touch-based input.