Scanner Radio tunes into the various police radio frequencies. As such data is public, it is legally allowed to rebroadcast such information on the Internet... and for people to listen to them. (UNLESS you are a criminal, really) The app allows you to tune in, through the Internet, police radio around the world, esp. those close to you. Most of it is pretty boring, like checking drivers license, or one guy going off duty or moving to another spot.
Interesting, but please delete it if you are a criminal. If you get caught with that in your phone, you can get an extra misdemeanor tacked on to your rap sheet.
Rating: try it