Another neat use for GPS: alerting you to speed traps. Trapster allows registered users to add speed trap locations on their website, and the mobile app alerts you when you drive close to one. The app offers customizable alerts for live police, red light cameras, speed cameras, and hiding spots that are often used. It’s currently in beta, and only offers support for AT&T, T-Mobile, and Sprint customers, though they’re working on support for other providers. You can check out instructions for installing it here. Thanks Mike!