You still need to open Shazam to enable Auto mode -- a feature that came to the iPhone version two and half years ago -- but that's a good thing. It's described as "battery friendly," but the app will stay active in the background, draining that bit more of your precious juice. You can at least leave it running while your favorite radio show is on, though, and if you just happen to get a perfect score on the music round at your next quiz night, fear not: Your secret's safe with us.