Seth Kranzler created "Steve Reich is calling," a delightful composition for two iPhones that celebrates (and parodies) legendary minimalist composer Reich's early phase music. This form of composition employs two or more identical phrases of music played at slightly different tempos so that they shift in and out of phase. Reich's most famous phase music compositions are "Clapping Music" (1972), "Piano Phase" (1967), and the fantastic tape music pieces "Come Out" (1966) and "It's Gonna Rain" (1965). Listen to the latter two below.