Taking the Fossil Sport on a Hike – Testing GPS and Heart Rate Accuracy

Fossil Sport Smartwatch
Fossil Sport Smartwatch (in red)

I’ve had the Fossil Sport since January but I haven’t had too many opportunities to use it on a hike until this month. Yesterday, I tested the built-in GPS of the Fossil Sport against the Garmin Instinct, a new hiking watch from Garmin that I’m also reviewing.

Quick Synopsis

  • The Fossil Sport’s Built-In GPS is Weak but It’s Connected GPS is Accurate
  • Both the Fossil Sport and Garmin Instinct Did Well for Heart Rate Accuracy
  • The Garmin Instinct is Great for Outdoor Workouts (great battery, screen, GPS)
  • The Fossil Sport is a Solid Smartwatch with Good Fitness Abilities for the Average User But Battery Usage Could Be Better When Using GPS

The Fossil Sport is the newest smartwatch from Fossil and one of only two watches on the market equipped with the new Snapdragon 3100 chip for Wear OS. My next comparison will be against the new Ticwatch S2 which is equipped with the older 2100 chip but today we’ll be looking at GPS performance and heart rate accuracy of the Fossil Sport versus the Garmin Instinct.

In order to force the Fossil Sport to use its built-in GPS I had to put the watch on airplane mode. This disconnected the Bluetooth connection with my phone. Otherwise, it will use the the GPS on my phone. I wanted to test the accuracy of its own built-in GPS and I’ll be updating this article with results of future tests use its connected GPS abilities.

The Garmin Instinct is primarily a hiking watch (that also supports many other activities) and has been testing out great for me. It’s a Garmin Fenix alternative since it has many of the same features but at a more affordable price.

A bridge I encountered on my hike. It’s a fallen tree converted to a walking bridge.

I was hiking through a wooded, hilly park, on top of hills, in valleys, and on a very low-lying flood plain near a creek.

I used Google Fit and selected the hiking activity. I’m not sure if the Fossil Sport ever found my location and instead used my number of steps to calculate distance. That’s what I’m assuming anyway. However, the Garmin Instinct connected almost instantly.

It appears to me that the Fossil Sport relies on connected GPS even though it has its own sensor built in.

On a positive note, the screen on the Fossil Sport is quite readable outdoors, even in sunlight. It does have an ambient light sensor so the screen automatically gets brighter in brighter conditions. There’s also a sunlight boost setting that you can manually set. I didn’t have any difficulty viewing the screen while hiking.

Fossil Sport

Garmin Instinct

If you are a hiker, runner, or cyclist, I’d recommend using a watch with a transflective display like the Garmin Instinct has instead of an AMOLED screen like that of the Fossil Sport. For one, transflective displays are very easy to read in the brightest sunlight and secondly they consume much less power from the battery.

But the Fossil Sport isn’t marketed as a hiking watch so I’m not going to knock it for not being one. It’s a smartwatch first with some very good fitness tracking abilities.

Tip: Regarding heart rate accuracy, I’ve found that I have to wear the Fossil Sport a little higher up on my wrist than other fitness trackers. Actually, Fossil recommends wearing it this way during workouts. The HR sensor is much more accurate when wearing it higher on my wrist during gym workouts.

But let’s get to the Distance Results!

I actually did two separate hikes that day so I have the data from both to compare.

Hike 1 – 24 Minute Hike

Fossil Sport

Active Time: 23:54
Calories: 159
Distance: 0.31 miles
Average Pace: 0.79 mph
Steps: 878
Max HR: 111 bpm
Ave HR: 90 bpm

Garmin Instinct

Active Time: 24:04
Calories: 78
Distance: 0.40 miles
Average Pace: 1.0 mph
Steps: I forgot to look!
Max HR: 135 bpm
Ave HR: 92 bpm

Hike Two – 40 minute Hike

Fossil Sport

Active Time: 41:18
Calories: 275
Distance: 0.71 miles
Average Pace: 1.03 mph
Steps: 1981
Max HR: 132 bpm
Ave HR: 104 bpm

Garmin Instinct

Active Time: 40:41
Calories: 155
Distance: 0.84 miles
Average Pace: 1.2 mph
Steps: Again I didn’t write this down but they were similar to the Fossil Sport
Max HR: 140 bpm
Ave HR 102 bpm

So it looks like the Fossil Sport estimated about a tenth of a mile less for each hike compared to the Garmin Instinct. I gave the Fossil Sport 2-3 minutes to connect before I began moving. It may have found my location eventually but I never saw that it did. Again, I think it just used my step count to estimate distance.

I think I can take away from these tests that the built-in GPS on the Fossil Sport isn’t one to count on if you truly want a stand alone GPS watch.

The Garmin Instinct on the other hand did a terrific job estimating my location. Viewing my route on a map after both hikes, I can see that the Instinct followed me very well so I’m confident that the distance estimates I’m seeing from it are pretty darn good. No GPS is 100% accurate but the Instinct appears to be one of the best I’ve tested.

There is quite a difference in calorie burn estimates too. It’s been my experience that Google Fit estimates on the high side while Garmin is more accurate. Boy, I wish I burned as much as Google Fit says I do during my workouts.

Heart Rate Accuracy

Taking a look at the heart rate results, I think I’d have to go with the Garmin Instinct again. It actually did quite well during this hike and most wrist heart rate sensors struggle when I’m hiking. In other tests, the Instinct didn’t do quite as well as it did during these two. Maybe the difference was wearing it on my right wrist. I normally wear it on my left.

If you’re not getting good heart rate accuracy from your watch, you might want to try wearing it on your other wrist during workouts. Some watches I’ve reviewed do much better on my right wrist than my left.

The Fossil Sport did okay with my heart rate during most of the hike. The numbers I was seeing seemed reasonable. Not too shabby.

Battery Usage

Battery usage during the two hikes was considerably more for the Fossil Sport. The battery began at 100% and used close to 28% after about an hour and half out on the trails. The Garmin Instinct was also at 100% when I began and used less than 5% of the battery.

So, I guess the moral of this story is that if you want a great GPS hiking watch, take a look at the Garmin Instinct but if you’re looking at the Fossil Sport for an everyday smartwatch that also does fitness tracking, it does an okay job.

I do have to say that because the Fossil Sport has the latest chip, I expect better battery performance in the future. Google just released a low power GPS update to the Ticwatch Pro but I’m expecting it to come to other Wear OS devices and hopefully that will make a big difference.

The new chip is all about more efficient battery usage but many of those features haven’t been unleashed yet on the Fossil Sport. Check back because I’ll do more tests when and if those updates come.

Also, I’ll be adding connected GPS results in a few days. I want to do a second test against the Instinct and I’ll be wearing the Polar H10 chest heart rate strap so I can be more certain on heart rate accuracy of both watches.

Most people will probably be using the Fossil Sport when paired with their phone so I’m really interested to see how accurate the connected GPS is and if less battery is used. If it was constantly trying to find my location, that would probably explain the battery drain.

Hey, any excuse to get back on the trails! Again, I’ll be updating this article very soon with those results. And below are the updated results!

>>View the Garmin Instinct on Amazon for current price and availability if you’re interested.
>> The Fossil Sport is available on Fossil’s website.

And now I have the results back from some more tests, including heart rate accuracy since I was wearing the Polar H10. Again I was comparing the Fossil Sport against the Garmin Instinct.

For this test I chose a paved bike trail and an estimated distance of about 1 mile from my starting point to a railroad bridge. The trail snakes along a creek in a wooded area with few hills.

GPS and Heart Rate Results

Fossil Sport

Distance: .98 miles
Max HR: 125 bpm
Avg HR: 106 bpm

Garmin Instinct

Distance: .94 miles
Max HR: 126 bpm
Avg HR: 96 bpm

Polar H10

Distance: 1.02 miles
Max HR: 125 bpm
Avg HR: 99 bpm

So as you can see, the distances were fairly close. The Fossil Sport and the Polar H10 both used GPS from my iPhone XR but got slightly different numbers but still very close to that 1 mile estimate. The Instinct wasn’t far off either and looking at the path generated from the Instinct it did a very good job mapping my actual route.

Below is a map generated by the Garmin Instinct showing where I stopped under a railroad bridge and then turned back and stopped the test. It nailed it! That’s exactly where I stood. There are other examples when I briefly walked off the path to take photos of the creek and it got that too.

One my way back I used Strava on the Fossil Sport so I would have a map of my walk. It did a great job as well showing the route I truly took along the trail. See the image below.

Looking at the heart rate data both watches did good. Max heart rate on all three devices, the Fossil Sport, Garmin Instinct, and Polar H10 were nearly identical. The average heart rate was a little higher on the Fossil Sport than the Polar H10. The Instinct did a little better on average heart rate.

Battery usage on the Fossil Sport using location from my phone was about the same as my first test trying to use the built in GPS.

Conclusion

I’m disappointed that the built-in GPS on the Fossil Sport doesn’t appear to be very strong on its own. You’ll probably need to take your phone with you if you’ll be using the Fossil Sport for outdoor workouts.

The good news is that the Fossil Sport did pretty darn good when paired with my phone at estimating distance and measuring my heart rate. There are certainly better fitness watches out there but as a Wear OS smartwatch that also does fitness, it’s good.

If you’re someone that wants to use the watch to record your lower intensity workouts and walks, it’s fine for that. If you’re a hardcore runner, you’ll want to look to something else.

I would like to see better battery life when using GPS on the Fossil Sport though. Maybe we’ll see that soon with future updates.

I’m impressed with the Garmin Instinct. While it might have slightly underestimated my distance, I can clearly see that it was extremely good at following my actual route. If you want a good hiking watch then the Instinct is something you should be looking at.

>>View the Garmin Instinct on Amazon for current price and availability if you’re interested.
>> The Fossil Sport is available on Fossil’s website.

So overall,