Frequently Asked Questions

WatchOS 10 GPS Issue during open water swim

It has come to our attention that the Apple Watch Ultra has demonstrated severely degraded GPS performance after updating to WatchOS 10. We have filed a bug report with ID FB13192409 

In the meantime, the following solution may correct the issue. 

If your watch is displaying poor results after updating to WatchOS 10, and after performing the steps above update, please contact support so that you can send us corroborating material which we can forward to apple.

WatchOS 9 Track

WatchOS 10 Track

Above images show two swimmers who swam together, one with watchos 9 and one with watchos 10 both on the Apple Watch Ultra. As you can see, the watch demonstrates significantly worse tracking. After analyzing the data from these and many other swims, we have found that the GPS does not report data correctly, with GPS points declaring invalid positions AND invalid accuracy. We are actively working to get this problem resolved with Apple.

Hey, something isn't quite right about my last swim. 

Occasionally, the app gets excited and tries to load the swim before all the data is transferred over. So you might see a zero distance, or the map is missing.  The first step is to reload the data for that swim, as in the first video below.

The next step is to reload swim data by pulling down the main screen, as in the second video. If that doesn't work, then you may want to try advanced support options below.

How does Open Water Swim track my Swim?

Open water swim uses GPS to track your swim location and distance. It uses Apple Watch sensors to track your heart rate and swim strokes. It relies on Apple's Calorie estimations for calories burned.

How come the track isn't exactly right

To track your swim properly, it is important to have your wrist at the surface or above the water for some period of each stroke. This isn't an issue if you swim in free-style (front crawl) stroke, since your watch will surface each stroke. However if you use breast stroke, it's possible that your wrist remains submerged for a significant portion of your swim. If that's the case, make sure you lift your wrist to the surface of the water when you move your hands forward during the stroke. Or you can occasionally raise your wrist above the water in any fashion that suits you.  The Apple Watch Ultra has dual frequency GPS and in our testing, it has had much better GPS tracking, and therefore, much better accuracy.

How come my heart rate tracking isn't very good

Heart rate tracking depends on several factors, but the one that you can adjust is the fit of your Apple Watch: too tight or too loose and you won't have succesful readings. As you swim, you can view your heart rate graph starting in v1.6 so you know how good your heart rate tracking is. If it's not going well, try adjusting the fit of your watch by loosening or tightening it. And remember, water will "tighten" some bands, so make sure the fit is adjusted while the band is wet (in the water). And cold water will restrict the flow of blood to the skin of your wrist, so your readings will likely be worse in cold water. Check out the video below for more tips on getting a better heart rate reading.

Hey, I don't see the water temperature when I swim

First of all, temperature reading only works on the Apple Watch Ultra. That’s because that’s the only watch with a temperature sensor.

And then second, if you DO have an ultra, then what is likely happening is that you are not triggering the sensor. To trigger the sensor, you do need to get the watch a little deeper in the water, something over 3 feet usually does the trick. If you love having the temp (and I know I do), then after your start your swim, and at any point you want a temperature reading, go ahead and do a little dive under the water. Once you hit the right depth, you’ll see the temperature appear on the top right of the watch.


Advanced Support

If you can't get something to work properly, whatever it may be, then this is the section for you. Try each of these steps and then check if your problem is resolved after each step. Do not proceed to the next step unless the previous step DID NOT SOLVE YOUR PROBLEM. Some of the steps may cause you to lose data. If that's the case, that will be listed as a possible side effect.

These steps should not cause data loss.

Restart your Apple Watch by following these directions provided by Apple

Restart your iPhone by following these directions provided by Apple

Although this should not result in data loss, you will have to set up your watch again.

Most of your swim data is stored in Apple Health. You will lose any location edits you have made, and any custom locations you have created. When the data is read by Open Water Swim, locations will attempt to be created automatically.

Anything else?

If you have a question, please submit it to support.

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