There are several points that must be kept in mind while selecting a GPS device. The most important is the purpose. You must buy a GPS unit that meets your requirements. There is no point to buy a GPS device that can work well as a navigation system in a car but will have very little use for a hiker.
Depending upon the purpose, you can buy the following GPS units:
1. For hiking: The best GPS device for hikers is one that is light, easy to carry, compact, and weather resistant. Ideally it should be handheld and should have WAAS that is Wide Area Augmentation System. This boosts the GPS accuracy to 10 feet.
It should be able to give you readings regarding your location, elevation above sea level, time, satellite location and signal strength. It should also enable you to calculate the distance that you have traveled; record your path as a set of waypoints; and give you the ability to retrace your route.
It should also allow you to upload maps and data from your PC. If possible, you should go for a GPS that has 12 channels to catch satellite signals in forests and hilly areas.
2. For jogging and physical fitness: The GPS device should be able to indicate speed, distance, heart rate and time. It should have a computer interface that allows loading of maps and new fitness schedules. It should be shock resistant and weather proof.
3. For driving: While choosing a GPS for your car you can select a handheld GPS device, a fixed GPS navigation system or a PDA. The features to look out for are: street mapping, large display screen, computer interface and external antenna compatibility. A fixed system will have more features and will be more rugged as compared to a portable device. Another downside of a portable system is that the voice instructions are often lost if the car’s music system is running. 4. For boating and other marine applications: The GPS device in this case should have features like: marine mapping, active sonar tracking, back tracking, computer interface and waterproofing.
Your next step should be to examine the products available in the market. For instance, if you want to buy a GPS unit as a hiking companion then you should compare the features of different hiking GPS devices. Select the one that meets your need – from the point of view of features and price.