The beauty behind a Handheld GPS unit is that it allows you to carry the world in the palm of your hand - literally. Handheld systems are usually lightweight and not much larger than a standard postcard. Due to the fact that they are easily portable and often shock and water resistant, they are particularly suited to hiking, biking and camping trips.
Handheld units work by storing the coordinates of chosen locations which are entered by a user prior to or during their journey. With the aid of global satellites, these coordinates are then used to plot a specific route from one destination to another. Possibly the only drawback to handheld systems is the fact that in most cases their mapping ability is somewhat limited. Prior to selecting a model it is therefore advisable to check how many maps come with the unit so as to limit the expense that will need to be spent on purchasing extra maps in future.
Top manufacturers of handheld systems include names like Lowrance, Garmin and Magellan . Standard features of handheld systems differ according to make and model. The most basic models like the Standard Garmin eTrex usually have few if any map data bases and are therefore used purely to plot a route from one destination to another. They are perfect for camping trips and hiking expeditions where it is necessary to constantly keep track of your location.
Mid-range versions are usually fully waterproof and contain an adequate map database of cities and towns. As a rule they also have a built-in altimeter and a twenty-route memory. A good example of a mid-range would be the Garmin Legend which incorporates all the basic features as well a few extras.
Sophisticated models will usually be equipped with useful extras like barometers, tidal calculators and compasses. They will also generally have more extensive memories and therefore store more waypoints. Garmin once again offers a number of highly developed units like the Garmin GPS III Plus and GarminGPSMAP 76S.
As far as other leading brand names go, the Lowrance Globalmap 100 is renowned for giving accurate readings regardless of location or terrain, while Magellan presents one of the few color screen models available in its SporTrack Color system. Bear in mind the fact that although more advanced units may be equipped with additional features, they are also often more complicated and difficult to use. In addition, you can expect to pay far more for the additional extras which in many cases are not even necessary.