“Why does your phone show that our hike was five miles and mine shows four miles? Last week my phone showed over 800ft more in how far we climbed, why are these so different?.“
If you’re a frequent hiker, rock or alpine climber who uses their phone to track activities, you’ve likely experienced situations similar to the one above with great discrepancies in the data accuracy of GPS apps. While it is convenient to download an app and rely solely on the data provided from your smartphone, this article may serve as an eye-opening experience about what you’re missing out on. If you truly want to gain accurate measurements of your outdoor activities, it’s time to ditch the GPS apps.
Accuracy
There are numerous reasons why you might see inaccurate data from a GPS app on your phone and although tracking the distance of an activity might seem straightforward, to do so accurately is actually quite a complicated and sophisticated process. The main issue with hiking and climbing is that relying solely on GPS data to track hiking and climbing is mostly a guessing game of piecing together data points that may or may not be accurate based on external and environmental factors (which is reflected both in distance and elevation gain/loss errors).
Of all activities one might record, hiking and climbing may present the most difficult challenges to GPS exclusive measurements. Environmental factors such as trees, cloud coverage, mountain peaks, cliff overhangs, canyons, valleys and more will block GPS signals from being communicated clearly from your device to a satellite, making it nearly impossible to ensure accuracy.
To the rescue – COROS GPS watches. Built into every COROS GPS watch is a barometric altimeter sensor that has the ability to measure the air pressure in your environment. With proprietary algorithms, COROS watches are then able to take into consideration data from not only your barometric altimeter and GPS, but also data fields such as cadence and average stride length in order to piece together the gaps and provide the most accurate measurement possible, even when GPS data isn’t reliable.

Training
A popular Peter Drucker quote reads “You can’t manage what you don’t measure”, and if you don’t measure something accurately, how can you expect to manage it?
Whether you’re a beginner, amateur, or expert – if you are looking to improve it is important to have accurate data to rely on. In addition, many hikers and climbers are incredibly surprised to see how much insight can be provided from an onboard heart rate monitor built into all COROS watches.
This can help break down the training load of an activity, let you know how you are performing compared to your baseline, or even provide insight as to how your body responded to a tricky pitch or steep incline on a route. Recording and reviewing this data is a paramount step towards improving your performance.
Real-Time Feedback
One of, if not the biggest advantage(s) of a wrist-based GPS watch is that you can access immense amounts of data at any moment, without having to fumble around with a phone. No matter the data you’re interested in (Slope %, Elevation Gain/Loss, Current Altitude, Checkpoints, and much more), by simply lifting your arm you’re able to gain an understanding of your current situation to assess the best route forward.
This not only saves time and energy but is also much safer than the alternative.
Accessibility
When you’re hiking or climbing, the last thing you want to do is take your eyes off of the wall/trail, especially with technical routes. Rather than scrambling to take your phone out of a pocket, waistband, or pack (and hoping not to drop it), glancing down at a GPS watch takes less than a second for you to see the data you need.

Navigation and Wayfinding
On all of the COROS APEX and VERTIX watches, you also have the ability to use route navigation directly from your wrist. With additional features such as “Route Deviation Alert” and “Back to Start”, there’s no longer a need to stop every quarter mile to make sure you’re still on route, nor will you ever have to worry about how to get back to the trailhead, your car, or house.
Altitude Features
On top of all the aforementioned benefits, all COROS watches have a “Storm Alert” feature that can be toggled On/Off at your convenience. For anyone that routinely spends time above 10,000ft, you know how quickly the weather can change and how valuable such a feature can be.
With the COROS APEX Pro and VERTIX 1/2, you also will have access to the “COROS Altitude Acclimation Evaluation System”. This system collects the SpO2 data and evaluates the altitude acclimation level for climbers and hikers when the elevation is above 2500 meters or (~8250ft). Climbers and hikers are given more quantified and accurate info and are under real-time monitoring and notifications to effectively prevent altitude sickness.