Global Positioning System technology was originally developed for use by the military, to help soldiers, sailors, and pilots find their way in unfamiliar terrain quickly and effectively. A GPS device uses 3D positioning information from a network of thirty satellites orbiting the Earth to tell you where you are. The most basic models (now out of date) would simply provide your coordinates – it was up to you to plot them on a map. Today's more sophisticated models offer a variety of maps and interactive overlays that are useful for any number of applications.
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There are so many uses for GPS systems that they have become an indispensable technology for millions of people. GPS systems are most commonly used by drivers, through in-car navigation systems that ensure you can never get too lost for too long. These GPS navigation systems can provide to and from locational directions, real-time traffic warnings and updates, and show you the location of helpful stops, including gas stations, malls, schools & parks, and many more. Newer models incorporate MP3 and DVD options into one convenient package.
Handheld GPS devices are helpful for those who travel by foot, or are active in the outdoors. Simple mapping tools, identical to the ones in automobile GPS, tell you where you're going. GPS apps for hunters can provide an overlay that shows terrain features and game trails. GPS apps for fishermen can give weather and tide information, as well as navigational depth charts. The number of helpful applications grows each day.
Display Size – For use in a car, you will want a large bright screen, with easily-accessed control buttons. For handhelds, a large screen is a convenience that may be superseded by the need for portability and durability.
Map Resolution – Street level maps are the ideal level of resolution, but some manufacturers charge extra for this level of detail. Portable models can usually be connected to a PC, and the necessary maps can be downloaded at your convenience.
Accessories – Voice-activation and hands-free technology is perfect for drivers who want to be able to input information without sacrificing safety. A unit with a more powerful antenna will improve signal reception and be quicker to respond when powered up or regaining contact. Alternate mounting kits can provide additional convenience in unit placement. Additional maps, applications, and overlays are often available for purchase, providing greater versatility.
The best advice is to pick a GPS device with the capabilities that best suit your individual needs – let your lifestyle be your guide.
Garmin, Magellan, and TomTom are the three most popular automotive GPS systems – they each have a large number of choices available, and higher end models include all of the latest accessories. Garmin and Magellan also have numerous entries in the market for handhelds, including fishing and marine devices.
Buying Guide
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