Shazam is a smartphone app that can identify nearly any song playing on the radio, even over the din of a coffee shop. It’s been downloaded more than 200  million times and become modestly successful; by steering buyers to iTunes, it generated about $24  million in revenue for the 12  months ended June  2011, the most recent figures available. Here, the startup’s data illustrate how and when people discover hits.

Data: Shazam; Photographs by Stuart Wilson/Getty Images; Brendon Thorne/Getty Images; Bobby Bank/WireImage/Getty Images