Google Play Music has been update for Android devices and it brings a new feature for subscribers to the services unlimited plan. Now you have a new Sound Search feature that allows you to have the app listen to music that is playing and it will identify it and take you to that song in the service so you can add it to your library. Because subscribers can add and download music to their library without actually owning the content (it is digitally locked to your account), the search feature is a quick way to add music to your library on-the-fly without having to make anything more than the $9.99 monthly subscription.
If this new Sound Search feature sounds familiar, the concept has been around quite some time. Shazam is probably the best known of these types of services and they still are around. With the inclusion of this type of feature in Google Play Music and other premium services, a stand alone app is starting to make less sense.
The update to the app is version 6.1.2116T for those who are keeping score at home and it is in the Google Play Store now. If you have the app installed, it could be a day or two before you see the OTA update.