GPS Swim Goggles – First Ever GPS Track For Open Water
This was a first for me, and possibly the first ever GPS track recorded by a member of the public for open water swimming using commercially available goggles rather than a GPS sports watch. (I’m sure you’ll let me know below if not!)
I recorded this a couple of weeks ago with the Holoswim 3 Pro goggles that the brand sent me to review. However, the smartphone app won’t be able to export the GPS part of the data for a few more weeks, so Holosport had to help me get it manually through their web dashboard, and here it is compared to the Apple Watch Ultra 4 (not 3, as shown) and the Garmin Fenix 9 Pro.
GPS Accuracy Thoughts
The dcranalyzer correctly points out that the track is less accurate than the Garmin and Apple, but I’m unsure if an average 17.8m distance discrepancy from the other two devices looks right, although it would be in places for sure. The accuracy isn’t too bad, considering it is swimming, and I’ve definitely seen far worse GPS tracks from every brand, including Garmin, on this exact same loop over the years.
Perhaps I introduced an error by starting every device at exactly the same time in the car park before walking and setting off; I wanted to make sure each device had an excellent fix before starting. So I may have eliminated one source of error but created another.
I’m not sure which Garmin or Apple track is most accurate. If I had to bet, I’d err toward Garmin this time, since a true OWS GPS track can’t be as jagged as the one Apple shows (green), so compare the red line to Garmin’s blue one.
Technical Details
The GNSS chipset used is Airoha AG3335M, which is the dual-frequency model that supports all major constellations: GPS, Beidou, GLONASS, and Galileo.
Apparently, there has been a GPS accuracy update since I did this test.
General Thoughts
I definitely prefer the Holoswim goggles to FORM. They look more like proper goggles and, for me, fit perfectly. More importantly, the weird field-of-vision restriction from FORM just doesn’t happen here, as Holoswim uses a different HUD image-projection design. Also different is the metric display, which is over a much bigger area (which you may or may not prefer – I don’t mind either way), and the pixel resolution is better on Holoswim.
Holoswim also has a heart rate monitor armband. Fine. However, you can also attach it to the swim goggles and put it under your swim cap to gather HR from the head/temple and beam it live into the goggles. This doesn’t work for me yet and is due for release in a couple of weeks, and I’ll probably have a more detailed review around then.
There’s always a but.
In this case, the FORM ecosystem is better than Holoswim right now if you are using it as a swim training platform for performance and technique analysis.
The Holoswim goggles are cheaper than their top-end FORM equivalent, but FORM now also has a light version. I’d say Holoswim is worth taking a punt on if you are a new adopter and like your tech. If you’re looking for a more serious training aid, I’ll come back in a couple of weeks with a more concrete view on where the brand is after their October update.
HoloSwim 3 Pro Smart Swim Goggles
GPS and HUD Swim Goggles for OWS and Pool
+other retailers
Quick answers
Is this the first public GPS track recorded by swim goggles?
As far as I know, yes, recorded with the Holoswim 3 Pro in open water rather than a GPS sports watch.
Which GPS chipset does the Holoswim 3 Pro use?
The Airoha AG3335M, a dual-frequency chipset supporting GPS, Beidou, GLONASS and Galileo.
How accurate is the Holoswim 3 Pro's GPS track compared to a sports watch?
Less accurate than the Garmin Fenix 9 Pro and Apple Watch Ultra 4 tracks recorded on the same swim, though HoloSport has since pushed a GPS accuracy update released after this test.
Last Updated on 30 September 2026 by the5krunner
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tfk is the founder and author of the5krunner, an independent endurance sports technology publication. With 20 years of hands-on testing of GPS watches and wearables, and competing in triathlons at an international age-group level, tfk provides in-depth expert analysis of fitness technology for serious athletes and endurance sport competitors. ID
