Shazam, the popular music discovery application, has added significant social networking and sharing features.

The app, which allows iDevice users to identify and tag songs simply by listening to a few seconds, has not offered any sharing options up until this point. A list of tagged songs is then recorded within the application itself, along with links to the iTunes Store, track and album reviews, artist biographies, and even more trivial information ranging from discographies to song lyrics.

Version 4 of Shazam adds a new feature called Shazam Friends, allowing users to share their tagged tracks with friends, see what their friends are listening to, and look up and purchase tracks directly from the iTunes store. The app now integrates with the likes of Facebook and Twitter, allowing users to easily find others who are discovering similar music.

Shazam for the iPhone and iPod touch is available from the App Store in two versions: the free version of Shazam allows users to tag up to five tracks per month while Shazam Encore ($6) provides unlimited tagging. A separate iPad version is also available but has not yet been updated with the new Shazam Friends feature.