If you own a smartphone, you've more likely than not used Shazam. The app, which identifies songs by "listening" to their audio fingerprint, was one of the earliest and best ways to wow friends in the days when iPhones were still new to the mobile market. These days Shazam contains a hodgepodge of features. Tagging a song can quickly pull up a YouTube video, for instance. And if you happen to tag a TV show? You'll see what music is playing, cast and crew information, and other details that save you a trip to IMDB.

The new Shazam is always listening

Today, Shazam is putting renewed focus on tablets with the launch of a revamped iPad app that brings with it some exclusive features. One of those is continuous tagging. No longer do you need to tap a virtual button for Shazam to start up its identification process. Instead, Shazam for iPad is constantly listening for music, TV, and anything else it can identify in a matter of seconds. Even when you close the app, it keeps attuned to potential audio fingerprints, but not in secret; a pulsating status bar appears at the top of the iPad letting you know that Shazam is still active — not unlike Skype, the regular phone app, or other software that calls on the microphone when in the background. It's worth noting that auto tagging can be toggled off for those who prefer the old approach. The company told us that battery impact should be minimal, as a test device kept running for two days despite constant tagging.

Shazam has also added geography-based activity streams to the iPad app. The device's extra screen real estate allowed developers to incorporate a global map that lists popular tags throughout the world at any given moment, with TV shows included in US results. A coverflow view collects your recent tags for easy reference at the top of the screen. Below that, you'll see a realtime listing of trending songs. And for the karaoke fans among you, Shazam now displays fullscreen lyrics (courtesy of LyricPlay) in time with whatever music is playing. Song links for Rdio and Spotify have also been added to the app. Shazam for iPad will be available today from the App Store. The company plans to test auto-tagging and other new functionality on the tablet first, but says they will eventually make the transition back down to iPhone and Android in the future.