GPS has a variety of applications on land, at sea and in the air. Basically, GPS is usable everywhere except where it’s impossible to receive the signal such as inside most buildings, in caves and other subterranean locations, and underwater. The most common airborne applications are for navigation by general aviation and commercial aircraft. At sea, GPS is also typically used for navigation by recreational boaters, commercial fishermen, and professional mariners. Land-based applications are more diverse. The scientific community uses GPS for its precision timing capability and position information.

Surveyors use GPS for an increasing portion of their work. GPS offers cost savings by drastically reducing setup time at the survey site and providing incredible accuracy. Basic survey units, costing thousands of dollars, can offer accuracies down to one meter. More expensive systems are available that can provide accuracies to within a centimeter.

Recreational uses of GPS are almost as varied as the number of recreational sports available. GPS is popular among hikers, hunters, snowmobilers, mountain bikers, and cross-country skiers, just to name a few. Anyone who needs to keep track of where he or she is, to find his or her way to a specified location, or know what direction and how fast he or she is going can utilize the benefits of the global positioning system.

GPS is now commonplace in automobiles as well. Some basic systems are in place and provide emergency roadside assistance at the push of a button (by transmitting your current position to a dispatch center). More sophisticated systems that show your position on a street map are also available. Currently these systems allow a driver to keep track of where he or she is and suggest the best route to follow to reach a designated location

There are a number of different applications for GPS usage. Here is a good post to some of the benefits of using gps tracking in a business environment. http://www.crowtracker.com/top-5-reasons-start-using-employee-location-tracking/

Global Positioning Systems (GPS)

Click on the link below for 19 different applications:

http://www.fws.gov/data/gisapp.html

GPS has normally used in personal tracker, vehicle tracker;
With the use of GPS Personal Trackers, loved ones will be in control from anywhere with full access to real-time location information, only one SOS button away from emergency help. With the use of GPS vehicle Trackers, it is confident knowing you can locate your valuable asset at any time.

Source(s):
http://www.meitrack.net/child-gps-tracker-mt90-to-ensure-your-childs-safety/
http://www.meitrack.net/vehicle-gps-tracking-system-helps-you-manage-your-fleet-efficiently/

Here is a huge list with best of them.