GPS units have gained acceptance amongst hikers and backpackers over the past several years. While the usual navigational gear (like a map and compass) should be brought on backpacking trips, a GPS unit can make exploration easier, and tracking your adventures simple.
There are a variety of GPS options available on the market to meet a variety of needs for backpackers, hikers, outdoorsmen and explorers. Choosing the best GPS receiver is dictated by your specific needs, and what you plan on using it for, but because technology has advanced considerably over the years, high quality GPS units with a wide variety of features are available at accessible prices.
Choosing the right GPS unit can be a fairly daunting task, so settling on a few “must-haves” will make the decision easier.
For most hikers and backpackers, weight is always a consideration. GPS units will add a little weight to your backpack, with most units coming in between 5.3 and 7.5 ounces (16 ounces = 1 pound). GPS units may be fairly light, but because many GPS receivers are fairly similar in features, weight can be a large deciding factor.
Ability to Store Maps?
Lower end GPS units may not include the ability to load maps within the unit. It's advisable to bring paper maps regardless of whether the GPS unit has map capability built in or not, but having them included does add quite a bit of convenience so you won't have to be constantly pulling out your maps for reference. Maps for GPS units are generally sold separately, so be mindful of these additional costs when considering mapping functionality.
Maps can consume quite a bit of memory, so make sure the unit will have enough for your intended purposes. The amount of memory varies greatly from model to model. Many only have 20 megabytes of memory, while more expensive models have up to 500 megabytes or more. A nice feature is to have a memory card slot, allowing for expandable amounts of memory.
Number of Waypoints
Waypoints are used to plot your journey, so the number of available waypoints will make your routes more accurate. Make sure that your GPS can store at least 500 waypoints. The majority of GPS receivers now provide for 1000 waypoints, so this may not be too big of an elimination item.
Number of Routes
You'll want to store a fair number of routes in you GPS receiver, so obviously the more the better. You can get by with 20 routes, but will likely want 50 or more.
On mountainous trails, an altimeter often times tells more than knowing your point on a map position. Not all hiking GPS units offer altimeters, so if knowing your current elevation is important (so you know how much of that climb you have left), make sure your new GPS has a built-in altimeter. If the GPS receiver has mapping capability, your elevation can be attained from the map, however a barometric altimeter yields more accurate elevation readings.
Screen Size and Color
Most GPS receivers now feature color screens which makes it easier to read maps and information than models which used black and white screens. Larger screens make it easier to read, but can also add to the overall weight of the device.
Bringing spare batteries is a must, but longer battery life is important for convenience, and will save weight, if you would otherwise need to be carrying multiple sets of spare batteries.
Most modern GPS units feature WAAS-enabled 3 meter precision. Wide Area Augmentation System (WAAS) is a system which utilizes both satellites and ground based stations that provide for more accurate positioning. A WAAS GPS receiver can give your location within three meters, at least 95% of the time. Because WAAS 3 meter precision is fairly standard amongst GPS receivers, this really isn't a big consideration in narrowing down your choices, but make sure it's there.
Receiver and Antenna
Hiking is often under tree cover or in valleys. Having a 12 channel parallel receiver and an external antenna make it easier to receive a signal under less than optimal conditions.
Many of the higher end GPS receivers offer a variety of features that may or may not be of any use to you, including games, two-way radios, and built in digital cameras. Be aware of what you are paying for, and whether or not the additional expense is worth the additional features.