GPS Watch Background
Small electronics that track the distance and speed of athletic efforts have a relatively short history and are occasionally misunderstood. The field is remarkably broad and diverse, and some athletes are more accustomed to using devices like these than others. They are popular among road cyclists, for example. So if you are a devout roadie, you likely have friends and acquaintances who can give you advice about which features and functions to look for in a recording device. See also our Bike Computer Buying Advice.
Others, like mountaineers and backpackers, are far less accustomed to tracking their activity using GPS, and they may not know whether a GPS watch is the right choice for them. If you have gotten this far, but you aren't sure whether a GPS watch is exactly what you're looking for, consult our overview of outdoor electronics.
The devices we tested and describe here target a wide range of sports. We focused on running in our 2018 review update, but cyclists, hikers, swimmers, skiers, mountaineers, and outdoor enthusiasts of all types will find a device here for their pursuit. Some of the devices we tested are suitable for all of these activities. To help you sort through the field, we'll outline the different types of products available, describe the features, attributes, and accessories that will influence your choice, and walk you through how you might choose a watch for different sports.
Types of GPS Watches
The unifying theme in this article, and in our comprehensive review, is the presence of GPS receiver technology. To put it simply, a receiver knows exactly where on earth the device is. With computing power and temporal data, the watch can deduce speed and distance. Software, other sensors, and accessories take this raw data and generate a whole host of useful information for the consumer. In light of that, we can divide the entire field into three main categories.
Simple Training Watches
In this category, the GPS information is used to track your position for training purposes only. The device collects this information and displays speed, distance and other data that you can view in real time on the watch and analyze further after your activity. If your pursuits are always on trails or roads, this sort of device is more than adequate. These devices may have just the basics, or they may be full-function, highly featured training tools or anything in between.
Watches for Training and Everyday use
Recent years have seen the melding of GPS training watches, smartwatches, and fitness trackers. Some GPS watches also have smartwatch features, some have step and sleep tracking, and some have both.
If smartwatch capability is as important to you as an activity tracking, you'd be well served by the Apple Nike+ Sportwatch. The Apple is an advanced smartwatch that also does a great job tracking your runs. On the downside, it doesn't have great battery life and requires an iPhone to function.
Watches for Training and Navigation
Watches in this category have all the same functionality as a more basic device, but the GPS signal can also be used to navigate. If your passions take you off-trail, this kind of device may serve you well. The most basic form of watch-based navigation is some version of a track back feature. Imagine you wandered into the wilderness and weren't sure how to get back to your starting point. (Don't do this.) If you initially tracked your effort with your track back-equipped watch, you could simply activate this function, and your wrist would direct you back along your path.
More advanced, but just as useful, is some sort of pre-trip route planning feature. Many devices allow you to map out a route while at home and then follow that route using your watch. Even if you do not anticipate needing navigation features, many of these more advanced devices have other features that will appeal to higher-end users. You may choose a device like this even if you will never leave the road.
While the Suunto Ambit3 Peak has the most dialed-in navigation features of the watches we tested, the combination of extensive navigation capabilities, excellent activity tracking, and basic smartwatch function make the Garmin Forerunner 935 and Fenix 5 the best bets here. If backcountry navigation is your only priority, check out the Ambit3 Peak. But if you want stellar performance across the board, including navigation, it's hard to beat the two top Garmins.
How to Choose a GPS Training Watch
The first thing you should do to narrow down the field is to consider where you fall into the categories above. Are you only interested in a watch that will help track your training, or do you want one that will also be useful in your day-to-day life? Do you plan to stick to the track, roads, and trails, or are you hoping to navigate some less charted terrain? Wherever you land, you can find a device that will suit your needs, but be prepared to pay more for watches that do more.
Other Instrumentation and Sensors
Next, you will want to consider other instrumentation within the device. By definition, all GPS watches track three-dimensional position using the Global Positioning Satellite system, and they also keep track of time. Beyond that basic function, consider whether you need a built-in barometric pressure sensor. While GPS position data for latitude and longitude is quite accurate, altitude data from GPS triangulation is not as useful, especially in steep terrain. So, some devices collect more sophisticated and accurate altitude position data by sensing barometric pressure. This same sensor can be used to infer changes in atmospheric pressure associated with changes in weather. Almost all devices equipped with a barometer also have a thermometer, and virtually all of them display this temperature data.
If barometric pressure sensing and time recording are your only needs, you may be a better candidate for an altimeter than for a full-featured GPS watch. In that case, head over to our standalone altimeter watches review to find out who's crushing that category. (Spoiler: It's Suunto.) However, as we detail above, the Garmin Forerunner 935 and Fenix 5 also have excellent barometric pressure sensors and perform better than the Ambit3 Peak across most other metrics. The Garmin Forerunner 645 Music includes a barometric altimeter as well. You can't calibrate it like the top-shelf Garmin models, but it proved to be accurate enough in our tests to satisfy the average user.
Data Collection and Platforms
After sorting out what you want from your watch based on the information above, consider how you hope to manage the data your device generates. All the devices we tested display at least a little real-time and summary information on the screen itself. Beyond that, most watches will upload data for review on your computer. Some use proprietary data interfaces while others can swap data to other formats.
Assuming you're a data nerd like we are, which watch's data platform will suit you best? If you already have some type of fitness tracker, we recommend sticking to your current brand if possible. For example, if you already track your day-to-day activity with a Nike+ FuelBand SE, we suggest that you get an Apple Nike+ Sportwatch to monitor and record your runs. The learning curve will be short, and all of your activities can be collected and recorded together.
Perhaps you are trying to choose between the Suunto Ambit3 Peak and Garmin Forerunner 935 — both outstanding, fully functional watches that scored toward the top of our test group. Many consumers will wind up choosing the Garmin because they already have one of Garmin's other devices, maybe for their bicycle, and it's easier to keep their data all in the same format.
But what if one of the watches in our review sings directly to your soul, but you already use another device from a different manufacturer? Take heart, young runner. You can always use Strava to collect all your various data streams in one place.
Maybe you don't already have a brand or platform loyalty, but you might have friends who do. If you have a fitness community that can inspire and motivate your activity, linking your digital record books can provide further stoke. Or, conversely, maybe you want to avoid any possibility of your boss seeing that you tracked an activity while you should have been at your desk. (Of course, on all platforms, you can control who sees your activities and which information you display.)
Strava has a robust user base and collects information from all platforms. Most of the manufacturers in this review have apps that will seamlessly integrate with Strava. (Read: you don't have to upload or push files yourself.) But in this rapidly evolving industry, we recommend that you make sure your particular watch choice will integrate with Strava if that's important to you. Beyond Strava, some manufacturers have their own fitness communities, though these are sometimes less robust. Nike/Apple's system is proprietary and exclusive, but useful and widely used. Both Garmin and Suunto have social networks, though we've experienced the unique loneliness of being the only person populating our own Garmin newsfeed. Ask around among your friends and training partners. Perhaps one social media platform is more widely used in your circles, and that could, in turn, inform your choice of training devices.
Many users will be content with the instrumentation inside their GPS watch. However, there are certain categories of information that can only be gathered with an additional accessory that links to your watch wirelessly. Some of the GPS watches in our review don't have built-in heart rate sensors, but they can collect heart rate data when paired with a chest strap. These include the Suunto Ambit3 Peak and the Polar M400. Notably, the Ambit3 Peak and the M400 come standard with chest straps.
The high-end Garmin devices, including the Forerunner 935, the Fenix 5, and the Forerunner 645 Music, already track a bevy of running metrics, but they can capture even more data when paired with the manufacturer's Running Dynamics Pod. Essentially, this pod captures detailed information about your gait and stride so you can understand and improve your running form. We didn't test this piece of gear, but for those who want to analyze their running at a micro-level, it's an exciting option.
If you plan to use accessory sensors with your GPS watch, note that there are two major systems for communicating between the watch and the external sensor. Historically, most of the dedicated athletic devices used what is called ANT+ communication protocol. This is essentially a radio frequency with proprietary coding to guard against cross-contamination, for instance, in busy races. As long as the device is designed to process the data, ANT+ devices work with all ANT+ accessories and vice versa. The alternative to ANT+ is Bluetooth Low Energy (abbreviated BLE). The BLE standard is developed and promoted by the same outfit that standardizes telephone Bluetooth accessories, but regular Bluetooth and BLE are not currently cross-compatible. All of this may soon be a moot point. With more and devices using smartphone compatibility, standard Bluetooth communication is fast becoming the norm.
Right now, as noted, ANT+ is slightly more common on dedicated fitness devices like the models we tested. However, because of Bluetooth's brand-recognition and a BLE foothold in the world of pedometers and other casual activity monitors, it is predicted that BLE or even standard Bluetooth will win out in the long run. What does this mean for you? If you already have a training device and accessories, note which communication protocol is in use and consider your next purchase to standardize for yourself. If you are starting from scratch, the market is still wide open. Despite predictions that one of these platforms will win out over the other, you currently have at least a few options for each sensor type in each ANT+, Bluetooth, and BLE.
Once you have assessed your needs and wants, consider at least briefly the size and weight of the device you choose. Many manufacturers make products in a range of sizes, so if one of our reviews catches your eye, but you're put off by the product's size, check to see if you can get the same feel and function in one of their other products.
In general, the smaller watches in our review are more basic and have fewer features than the beefier models. However, if you're looking for a low-profile watch and you don't want to sacrifice functionality, two watches stand out here, and given their dominance in the field, it's no surprise that they're both from Garmin. The Forerunner 35 is one of the lightest models we tested, but it still features an easy-to-read screen and has a built-in wrist-based heart rate sensor. It's also much cheaper than the higher-end models, so we recommend this as an entry-level watch.
The Forerunner 645 Music (which also comes in a non-music version) is only a bit heavier than the Forerunner 35, and it doesn't overwhelm small wrists. The 645 has a significantly smaller diameter than its top-shelf sibling, the 935, while including most of the same features. Adding in the fact that this watch can store music and can be used as a contactless payment device, we were pretty blown away by the 645 Music's compact stature. It's a great option for users hoping to combine portability with high function.
GPS for Specific Sports
What do you get up to in the great outdoors? Your favorite activities will influence what you should look for in a GPS watch.
Runners have the most options. Running is one of the simplest forms of training, and it's the simplest to track of all endurance sports. You'll want your watch to display pace, distance, time, and perhaps some lap data for comparison. You may want to review your data afterward, and you may want to track your heart rate or your step cadence with a foot motion sensor. All of the watches in this review are appropriate for runners.
If you are only a cyclist, check out our comprehensive bicycle computer buying advice and review. However, if you also run or climb or ski, you can now most certainly use a wrist-mounted GPS device. First of all, you can simply add a shim and strap your watch to your handlebar for easy viewing. If you only need speed, time, and distance data, you have the same needs as a runner. However, if you wish to monitor bike-specific data, like pedal cadence or pedal power, you will need a more sophisticated tool and external sensors. The latest version of the Suunto Ambit, for instance, will readily process data from a power meter and the display and recording can be customized for cycling. We did not directly compare any of our wrist-mounted GPS trainers to the dedicated cycling computers, but it is conceivable that the most advanced of the former would surpass the functionality of at least some of the latter.
Swimmers have very specific needs. All need a device that is waterproof with an easy-to-read display. Outdoor swimmers need a model that will track distance and speed with GPS in addition to collecting stroke rate information. To measure indoor swimming, the watch needs to know your pool's length and must have a motion sensor sensitive enough to monitor each arm stroke as well as the acceleration associated with pushing off the wall. The best products on the market can do all of this and more. While we did not test for swimming acumen, our former Editor's Choice, the Suunto Ambit3 Sport, has gained favor as a swimming and triathlon tool. The Suunto Ambit3 Peak and the Garmin Forerunner 935, Forerunner 645 Music, and Fenix 5 also have swim tracking functions, though even the devices with wrist-based heart rate monitoring need to be paired with a chest strap to measure heart rate in the water accurately.
To track triathlon training and events, a watch must do all the tasks noted above. It's also nice if it can be programmed to seamlessly switch between sports and compile the data for review in sum and by individual sport. Again, the Ambit3 Sport has shown to be excellent for triathletes, and the Garmin Forerunner 935 and Fenix 5 are also favorites.
You are far less likely to track your data while alpine skiing, but many skiers are curious to review that data after the fact. Alpine skiers should look for excellent post-event processing and accurate speed, distance, and elevation data. Choose a model that has lots of storage memory and that uses a barometric sensor for altitude information. We hate to sound like a broken record, but the Ambit3 Peak and the high-end Garmin models are great choices here.
Nordic skiers' needs are quite similar to runners. You want to know distance, speed, time, and often heart rate. Given that, all of the watches in this review would be good options for Nordic skiers.
Backcountry skiers wish to track distance, speed, altitude, and occasionally various other performance metrics. The steep terrain they encounter necessitates barometric altitude measurements. Because backcountry skiing is inherently off-trail, navigational features are much appreciated.
Finally, consider interference with your avalanche transceiver, which we also review here. All electronic devices interfere with avalanche transceivers, and devices transmitting and receiving radio signals in close proximity to the avalanche transceiver interfere the most. GPS, ANT+, Bluetooth, WiFi, and BLE are all radio signals.
For maximum safety of you and your partners, ensure that your GPS watch can be configured to reduce or eliminate these signals. For instance, one of our test editors, an internationally certified mountain guide, and avalanche instructor, uses something like the Suunto Ambit3 Peak to record only barometric altitude and time data when it really matters. He thinks critically and sometimes justifies recording heart rate and GPS data. The most important thing is to know your technology, know yourself, and err on the side of making sure your transceiver is going to work when you need it.
Mountaineering and backcountry skiing have similar device needs. However, many times mountaineering takes place without avalanche transceivers. In this context, the above concerns with radio interference are of course eliminated.
While few rock climbers train with a GPS device, we predict this will change. Many climbers own a GPS training watch to track their skiing, running or mountaineering efforts, and they may wish to track exertion and time data similarly. In our testing, we have found that GPS data is virtually useless on a cliff, but altitude information can be interesting.
Hiking on flattish trails isn't much different from running or Nordic skiing. However, hiking off-trail and in rugged environments is more akin to mountaineering or backcountry skiing. Assess your habits and choose a watch that is suitable.