The following helped for me. Now I get acceptable tracks most time. Not good ones.
Before you go swimming sync your watch with Garmin Connect. Or with the Garmin App.
With the APP I am not really sure. This…
DerDembo latest software updates to 935 and 5+ seem to have fixed the OWS accuracy issues if you look at some of the other threads on here - as far as I can see they are sw problem not antenna based otherwise you would expect GPS issues on most activities not just OW swimming
already regretting the upgrade due to the Open water swim!!