Handheld GPS Information

GPS receivers for outdoors and those meant for cars are two different animals. Auto units have larger screens, come with cigarette-lighter adapters and have audible driving directions. They also lack features like altimeters and electronic compasses, but provide more information on traffic updates and highway routing.

Other options for use in your car include a PDA/GPS or smartphone solution or using your laptop in conjunction with a GPS receiver and mapping software. See our companion reports on auto GPS, PDAs and smartphones for more information.

Wrist-mounted sports watches often include a GPS receiver, which helps athletes track distance. These models, including the popular Garmin Forerunner series, are addressed in our report on sports watches.

There's a short overview on GPS satellite technology at About.com, from geography guide Matt Rosenberg.

GPSGazette.com keeps up with the latest news on GPS devices, though many of the review sites in Our Sources do so as well.

Aviation and Marine GPS

GPS units specifically for aviation use are available from several manufacturers. Excellent information about aviation GPS receivers can be found on AVweb.com (but you must register) and Avionix.com.

Marine-use GPS units offer extras like fish finders and resistance to salt water. GPSInformation.net is among the sites that include reviews of marine GPS.

Manufacturers' websites:

DeLorme

Garmin

Magellan

Mio