Do you need a GPS?
It's wise to be prepared when heading into unfamiliar territory, and a GPS can provide protection if conditions deteriorate. You may run into issues like bad weather reducing visibility, washed out trails, and poorly marked trails, which can throw you off your intended route. Fog, rain, or snow can all be problematic and make trail finding difficult. We have all more than once taken a "short cut" after descending a climb, following what was initially a pretty good trail, only to have the trail peter out and end up in an epic bushwhack back to the car in the dark. A GPS can help you navigate through unexpected conditions and get you safely back home.
Can a GPS replace a map and compass?
The tried and true method of navigating by a map and compass can't be replaced by a handheld GPS unit. We at OutdoorGearLab strongly recommend carrying a map and compass in addition to a GPS unit when in unfamiliar terrain. GPS units are great to use with a map to find location (using latitude and longitude). Maps don't run out of batteries or break if accidentally dropped off a cliff. As a result - they are a fail safe backup to any electronic device. For added protection, put your non-waterproof printed maps into a 8" x 11" waterproof LOKSAK bag. This will ensure that even in bad storms your map will stay safe and dry.
Why buy a GPS?
A GPS can provide valuable location-based information that you can't see with your own eyes. For example, marine GPS devices with charts show water depth, potential underwater hazards, and — most importantly — display your position in poor visibility conditions. Lobster fishermen in Maine use GPS to plot the locations of their traps so that they can fish in dense fog, heavy rain, or whiteout snow conditions. Hunters use GPS to mark the location of their kill, tree stand, or trailhead. Mountain guides will use the "tracks" function to mark routes up and down mountains. Some guides testing the units said they share routes on descent of the mountain via Bluetooth with fellow guides going up. For outdoor recreation purposes, GPS devices are most useful for displaying your position (which presumably can't be found by other methods) relative to your destination. Many love to spend their weekends looking for hidden treasures called "geocaches." Many devices tested (like the Garmin GPS MAP 64s) have pre-programmed caches located in your vicinity for a fun-filled weekend. Find out some other great uses for your GPS here.
Smartphone GPS applications
Most of us carry a phone in the backcountry. So why carry something else?
Answer: dedicated handheld GPS have better satellite reception, more powerful navigation features, and better battery life than smartphones GPS applications. They are ideal for extensive off-trail navigation in low visibility conditions. However, if you carry a phone and primarily walk on trails or travel on established routes (like rivers), a smartphone app is likely all you need. We recommend the Trimble Outdoors app for its navigation features (requires additional purchase of area-specific maps) and the Topo Maps app for the best value (iPhone/iPod only, download unlimited free maps before you leave). Based on our testers' extensive experience in the backcountry we've found that a GPS is most commonly used to identify or confirm our position briefly before we resume navigating with maps. For such applications, an app like Topo Maps works well and only costs $7.99. For most backpackers we suggest starting out with a GPS app and upgrading to a handheld GPS if it proves insufficient for your needs.
What to consider when buying a handheld GPS
In considering a new GPS unit you need to determine what kind of GPS you need, the features you want, and how much you're willing to spend. You don't want to purchase a GPS intended for car navigation when you intend to go hiking. Learn more about GPS types and their features.
Types of GPS Units
Car Navigation Systems: Used primarily as a navigational system in your vehicle, these units are either built into the car's dash, suctioned to a window, or mounted to the dash. They have great accuracy, a large screen, and easy-to-see color schemes. You can get from point A to B by simply typing in your destination and pressing "go." In our review, the Garmin Montana 680 seemed to be the best handheld that could be used as a navigation system in an automobile.
Aviation Navigation Systems: These units are designed for use in the air. These units feature aerial map views with flight plan, airport, and direct-to navigation information. If you're in a low-flying bird, these navigation systems will help you stay en route in a storm.
Boat-Based Navigation Systems: Any dedicated boatman has their trusty "fish finder" and GPS combo. These contain navigational and sonar technology. Coastal ocean and inner lakes maps help navigate large bodies of water while sonar helps to find prey lurking in the deeps below.
GPS watches and altimeters: There are a variety of watches that monitor fitness. Some fitness trackers are simple and just monitor the number of steps you take in a day. Others have a built-in GPS that can log your route information to show you where you've been, the altitude you've climbed or descended, and more. These GPS Watches are popular among trail runners, mountain guides, hikers, and backpackers. They are a great alternative to a handheld if you're just looking to go light but don't have nearly as many features.
Two-way Communication Systems: Some GPS handheld GPS devices are compatible with two-way satellite communication systems to communicate in remote areas with no reception. These are especially handy when planning long excursions into the backcountry and an emergency device is needed. Check out The Best Personal Locator Beacon and Satellite Messenger Review to learn more.
Hand Held GPS Units: We focus on these devices in our review. They are reliable multi-functional computers designed to log spatial data. They mark waypoints, track your route, make notes, geocache, pull up altitude profiles, and more. Small enough to wear around your neck or stash in your backpack, they are commonly used for on-land purposes. They are especially useful when you need a reliable unit that won't run out of battery quickly and can endure nasty weather conditions. An example of a truly trustworthy hand-held is our Best Buy winner - the Garmin eTrex 20x.
Handheld GPS Features
The features of a GPS unit is what sets one apart from the other. Some units come are loaded while others just offer the basics. Before buying a handheld, consider what extras you want and need.
Before we dive into the pros and cons for additional features, you need to understand what a basic GPS unit comes with. All the units in this review come with the following:
-Maps (ability to upload maps for paper-less navigation)
-Compass (electronic or differential)
-Trip Computer (logs motion info like speed, time, distance to the next waypoint, etc.)
-Geocache options (some come pre-loaded with many)
-Photo Viewer (some also have cameras)
-Track and Waypoint Managers (organize and store waypoints)
-Profile Options (select different ways to graph your information on the device - i.e. distance vs. altitude, distance vs. time, ect)
-Route Planner (use waypoints
-Sun and Moon (sunset & rises)
-Area Calculator (walk a perimeter and it will calculate the area)
-Satellites (Shows you the number of satellites triangulating your position and the strength)
-Best Fishing Days
-Proximity Alarm (set it to a waypoint)
-Location of closest cities
-Points of Interest (airports, hospitals, etc.)
-Tides Information (for the surfers out there!)
Touchscreen or Buttons?
Buttoned units are advantageous because you can use them with thick or thin gloves, batteries last longer, and they work in all temperature extremes. They are just more reliable. The downside is they lag in speed and it takes longer to type in waypoints. What it really comes down to is your preference. Do you prefer a unit that feels more modern and operates quickly? Or are you looking for something that is above all reliable?
Electronic or Differential Compass?
Electronic compasses are usually the cut-off point where manufacturers separate the basic units from the more powerful ones. An electronic compass shows you direction without having to move whereas a differential compass will not show your direction without movement. For some this is a great advantage. One of our main testers was a mountain guide that works on Mt. Rainer in Washington State. He mentioned that having an electronic compass is important for situations where you need to figure your direction without moving (say a whiteout when you're close to cliff edge). Many mountain guides will look for a GPS unit that has an electronic vs. differential compass because it makes navigating faster and easier. Does that mean everybody needs it? No. It is not necessary for the average recreational GPS user; it's just a nice add-on.
Another feature that defines the line between high and low performance devices. Altitude readings in handheld GPS units tend to be less accurate than latitude-longitudinal readings. A barometric altimeter using special sensors helps better calculate altitude. You can also use these altimeters to track weather patterns. This is especially useful if you are in the back country without access to a weather forecast. A great feature for better accuracy.
The addition of a camera, microphone, and voice recorder is a cool add-on to fully document adventures. You can use these media options to mark a waypoint in lieu of typing one in. We loved this option when looking back at our adventures and we can directly see pictures and videos of our route along the way. Furthermore if sharing your route information with friends they can use these pictures to ensure they are following the same track. This is especially helpful for those looking to buy a device for an outdoor guiding company or to conduct scientific surveys for an area. Many survey groups require photo evidence for an area and this a great way to keep everything in one place (as opposed to carrying a camera and later attaching the pictures to different waypoints).
Share Wirelessly and Smart Notifications
As technology gets smarter, so does the handheld GPS. High performing devices like the Garmin GPS MAP 64s have many sharing features. The first being the "share wirelessly" option. These devices come equipped with Bluetooth technology. With a compatible receiver you can quickly send track and way point files wirelessly to another device. Our main tester mentioned this is especially helpful if you have another group that is about to embark on the same route you just finished. In a matter of minutes you can sync up devices and share your route. We would recommend this for users intending to share track information with others.
Another great feature is "smart notifications." You can sync your smartphone to your GPS and receive text messages or social media updates on the unit. If you don't want to take your phone out of the backpack while staying connected, this may be an option for you.
How Do GPS Units Work?
Currently, there are 1,200 satellites orbiting the Earth. These satellites belong to a variety of countries and a number of government sectors. In North America, we receive signals from satellites managed by the U.S. Department of Defense. Higher performance units utilize satellite data from both the USA and other countries with private networks. These satellites transmit timing and positional data. Once a GPS receiver receives a signal from at least four satellites, the location can be triangulated. Units with higher accuracy can pick up transmitted data from more satellites. The most accurate units tested in this review include the Garmin Montana 680 and the Garmin GPS MAP 64s. These units had recorded accuracy within 10 feet which is awesome for a handheld. Trimble GPS units are more accurate (and more expensive) putting you within an inch of your actual position. These units are much larger and used to triangulate exact position.
The units tested in our review used two satellite networks. The USA manages the Global Positioning Satellite (GPS) network while Russia manages the Globalnaya Navigazionnaya Sputnikovaya Sistema (GLONASS) network. The GPS network accesses 32 satellites while GLONASS contributes 24 additional satellites. In addition, all handhelds have WAAS (Wide Area Augmentation System) compatibility to increase unit accuracy. This technology provides data to compatible receivers to augment their position. Signals from satellites are sent to WAAS master stations on land where augmentation messages are sent out. This message is sent to compatible receivers (like GPS units) which automatically corrects errors to provide a much more accurate estimate of location. GPS units that utilized GLONASS, GPS, and WAAS compatibility with a large antenna had the best reception.
Each manufacturer includes software designed to organize, analyze (though functions are very basic) and project the waypoints and tracks you collect with your unit. Garmin Basecamp is our favorite software because it's simple, intuitive, cross platform, and provides everything a basic GPS user needs. For example, you can easily display waypoints or tracks in Google Earth, a feature no other manufacturer supports.
Magellan Vantage Point is very similar to Basecamp in that it offers a comparable suite of tools. We, however, prefer Basecamp because it's slightly easier to use and Mac compatible. DeLorme models ship with Topo North America, a powerful and impressive suite of detailed topo maps for the Unites States. Although these maps are excellent, we found the software to be harder to use than Basecamp and Vantage Point. Performing basic functions, such as viewing an elevation profile of a route, requires more mouse clicks in Topo North America than in either of the other two programs. If you want to do some analysis, skip the included software and download an open source GIS.
If you choose to buy maps from a manufacturer, definitely go with 24k scale (Garmin denotes models with preloaded 100k maps by adding a "t" to the model number). All manufacturers offer aerial imagery downloads for around $30 per year, but this is often unnecessary because you can plan your routes in Google Earth and then send files to your mapping software and device. Satellite imagery is rarely necessary in the backcountry; we don't suggest paying money for it.
You can also download maps and satellite imagery for free and transfer them to your unit. A good source for free maps is the GPS File Depot. The U.S. National Agricultural Imagery Program (NAIP) shoots high quality, free aerial imagery for the entire continental U.S. every year or two. The United States Geological Survey's Seamless Data Warehouse has a wealth of free spatial data. And of course, most U.S. states have a website that houses spatial data. If you want the best maps spend some time tinkering with the free data. If you want something low effort be prepared to shell out around $100 for maps from a manufacturer.