A program that was an early favorite at the App Store has reached a milestone of sorts: Today the company announced that over 1.5 million people have downloaded and used the app.

“The Shazam iPhone application has had a phenomenal user response both in the number of downloads and the number of tracks being identified,” said Andrew Fisher, Shazam’s CEO. “The application taps into the user’s desire to discover, capture and share their music experiences and the success confirms our belief that music recognition will become a ubiquitous feature for all mobile phones in the future.”

Shazam offered iPhone users a 100% free tool to identify music as a song plays. If you’ve ever heard a song and wondered what the song was, this App works great. Simply let Shazam listen to a piece of the song and it will identify the artist and track name and display it. Songs are then linked automatically to available YouTube videos and to iTunes.