By swapping conventional map and compass, the hand held GPS units have significantly changed the exterior travelling. These handheld GPS units provide exact location, altitude, topographic and other data. Such GPS units could increase outdoor protection and reduce the possibilities of getting lost. In addition, it provides the traveler the actual information of location, which can be transmitted to the rescuers in any emergency. Hand held GPS units are fun to be used and now they have made possible a new sport i.e. geocatching. This is an outside treasure hunt, which examines the skills of direction finding for its user.

Outer hand held GPS units have many features in it such as color touch screen; moveable map; several turning points; trip details such as compass direction; speed and arrival time; altimeter; digital compass; time; alarm; camera and link with the computer. These outdoor handheld GPS units can be used in cars, aquatics or at aviation time. These units can be purchased by paying a price from $100 to $500 approx.

These equipments use the global positioning system, combined with the state of the art geographic technology. This is a portable and easy to use device for everyday use. GPS facility is provided in many other devices also such as GPS cell phones, PDAs and other navigational systems. The hand held GPS units have many remarkable features such as navigation support and land survey details. Few of the devices provide special information on geographic locations including historic and national landmark. Most of the outdoor lovers use these units to receive exact information about the location and other details while travelling.

The hand held GPS units have 3D maps, full colored screens, temperature readings and barometric pressure readings. For those, who love to do tracking or hiking, there is a waterproof GPS available for them. One should keep one thing in his/her mind that at the time of travelling, he/she should choose light weight hand held GPS units as these are portable and comfortable to carry. These are available in a collection of bright and beautiful colors that is essential while tracking or hiking in a park or forest. Dull colors should not be selected as they mixed up with nature and make it hard to relocate.

The hand held GPS units depend on at least three available satellites, having an average accuracy of within about hundred feet or thirty meters. If one wants to buy one of the hand held GPS units for using in daytime, then he/she can choose simple black and white screen but for night time and for poorly lit environments, colored LED screens are perfect. One should also examine the waterproof level of the GPRS unit while purchasing it. One can also use Internet for having online services to evaluate the prices of hand held GPS units according to their varieties, design, features and brands. In this way, he can buy an ideal hand held GPS unit. Make sure that one get the best deal as GPS devices requires big amount.