How They Work

Personal GPS locators work a bit differently from the GPS devices you might have seen mounted on car dashboards, used by boat navigators or in someone's PDA (Personal Data Assistant, like a BlackBerry). In those devices, the person looking at the device tries to figure out where he or she is by electronic maps. In a personal GPS locator, the wearer or the device isn't trying to find out where he or she is - he or she wants others to find out where the wearer is and get them the heck out of there.

Remember all those nifty "tracking devices" seen in science fiction shows and movies? GPS locators are those tracking devices come to life. They can look like cell phones, BlackBerrys or a watch or armband. The signal they send out is silent to anyone near the wearer of the GPS locator. The device itself dials and contacts any emergency number in the world, depending on what country the watch finds itself in.

The GPS locator then transmits information in text message or to a website that has been downloaded with specific GPS tracking software (available with the GPS locating device). It not only tells the rescue team or guardians where you are, but projects where you might be going. They often include information such as the date, time, speed, current location and projected heading (in case you are in a moving vehicle).

How Much

Depending on what kind of GPS locator you want, prices can range drastically, from a couple of hundred dollars to a couple of thousand dollars. Pull out all of your favorite comparison shopping tricks when deciding on a GPS locator. See how easy it is to use, what kind of battery it takes and how long it can go in between charges. Find out, too, if it has any kind of warranty and who you need to take it to for repairs.