Substantial

DopeTracks.com is the self-proclaimed "home of the best hip hop beats, producers and underground emcees on earth." Offering a collection of over 100,000 original beats and instrumentals, DopeTracks invites producers and MCs to show off their skills with the former uploading tracks and the latter adding vocals. These collaborations are then shared and rated on the site. Substantial built the iPhone app for the site, allowing you to record and share a verse on the go.

The DopeTracks app sports both a scratchpad for jotting down lyrics and a browser for sampling uploaded beats. Once a beat's been selected the iPhone acts as your mobile multitrack studio, playing the backing track while recording vocals. Portions of a vocal track can even be re-recorded until they're perfect, with the resulting take then being uploaded to the Dopetracks site. The app truly pushes the boundaries of what's possible in a mobile platform.