When deciding on which global positioning system (GPS) receiver is best for your specific needs, take some time to do a little homework online. GPS receivers are available with different types of maps with various levels of detail. You may also want to avoid some models with the high-end features that you really don't need, like a heart-rate monitor or a barometric altimeter. If you want better reception in areas where trees and buildings may obstruct the signal, select a GPS unit that utilizes a 12-channel or better parallel system.
The modern GPS receiver uses 24 NAVSTAR satellites to determine a single location to within a few feet. Choose a GPS receiver based on your particular needs. For example, a GPS unit that will be used in a vehicle only will not need to be waterproof, but a unit used for hiking or in the outdoors should be either water-resistant or waterproof. If choosing a GPS receiver for hiking, find one that has the wide area augmentation system (WAAS) function, which can more accurately fix your position to within 10 feet (3.048 meters).
The most popular GPS receivers offer basic features like an FM transmitter, Bluetooth® and the a text-to-speech feature which speaks easy to follow directions, like, "Turn right at Main Street," as opposed to, "Turn right in 200 yards." Screen size is important for maximum visibility, so look for a 3.5 inch (8.9 cm) or larger screen. Lighter GPS receivers will typically have smaller screens. Most GPS receivers will have a standard 20 route memory, though some units offer as many as 50 stored routes, and some models come with a memory card slot that can be expanded to store and recall a large number of travel routes. The number of waypoints that can be stored is also important, and a unit that guides you from waypoint to waypoint is essential for hiking.
If this is your first GPS receiver, look for a manufacturer that has a large selection of types, styles, and map scales. Most GPS receivers will have different types of maps for a specific geographic area already loaded. For instance, units sold or purchased in North America and Canada will typically already be pre-loaded with maps for that area.
Some GPS receiver features may not be available everywhere, so be careful to check all the details before making a final purchase. You can end up getting stuck in a traffic jam that did not show up because a particular feature is not available in a certain area. As with most high-tech electronic devices, the more expensive models will typically have better features, more available options, and more solid construction from better quality materials and components.