I asked the developer abotu that, and he answer that "If Garmin ever updates firmware on your watch model to support 3.1 SDK, we will surely add it to the list" ...it is buetooth problem, but for example vivactive4, fenix5+(and more more) are compatible. Is it possible to updating erlier watches software to 3.1 SDK...?
the app is here: https://apps.garmin.com/en-US/apps/53d9c500-614e-4e3a-88b6-9f65bc6a144a
Kitesurf is my favorite sport ever, many of many people waiting for app like that, I hope updating software of bluetooth is possible...
regards,
Kris