Juicy Development has released Police Scanner for iPhone, a useful tool for locating and listening in on police dispatch frequencies throughout the country. Over 500 EMS operations stream their dispatch communications on the Internet. Police Scanner for iPhone connects to these streams and allows listeners to stay informed.
While you're going to have to wait until June to get your hands on iPhone OS 4.0, app developers have already been tinkering with it for weeks, providing plenty of juicy details about the features buried within the software's code.