Shazam

Shazam is a free iPhone application that lets users identify songs using their iPhone. The user needs to keep the iPhone close to the source playing the songs. Shazam collects around 10 seconds audio sample and sends it to the Shazam server to identify the track. Using a proprietory algorithm, Shazam identifies the track and displays the track details like Title, Label, Artist, Album. It also provides links to YouTube videos or iTunes store if they exist.

The Shazam database is quite vast. Most of the songs are identified. It can even identify Hindi songs and to an extent Kannada songs.