Shazam

Shazam's music recognition service has been around a while but on the iPhone it comes into it's own. For those unfamiliar with it you can use your mobile phone to identify which music is playing. Say you're listening to the radio, or you're in a club and you want to who which track is playing you simply start up Shazam, press 'Tag Now' and Shazam 'listens' to the music for 15 seconds. It then queries it's database and within 60 seconds it'll tell you which track you were listening to.

The iPhone version is great. Most importantly it's free, but Shazam also returns a picture of the album cover, gives you options to Tweet your 'Tag', links to watch a You Tube video of the track in question or to buy it on iTunes. Every time you've tagged is then stored for future reference.

I've bought several tracks after tagging them in a bar or club. I've also used it for successful cheating in music based pub quizzes!

Every iPhone should have Shazam pre-loaded on to it!