Garmin should really embrace this. The alternative, relying on smartphone apps, will lock them out in the long run. The big advantage of buying dedicated hardware, like a Garmin bike computer, is having more control over your data.
I wish Garmin worked on their SDK and documentation — I wrote a quick app for personal use, and it made me appreciate folks who write Garmin watch apps much more. The documentation is incredibly bad, half the things I had to figure out using trial and error, and even then I wouldn't know how to build/test for other watches than the one I own. I'd have gladly worked on the app and put it in the store, I think it'd useful to some people, but I'd have to put far more effort than it's worth.
I have two Garmin devices: a watch and bike computer. Both are connected to the same app that collects data to a single Garmin Connect account.
I expected some synergy but I got nothing. When monitoring the same activity with the two devices you just gets dupes (for example, sum of the distances measured by the two devices). This is worse than if I had 2 devices from 2 different brands.
Right, Garmin doesn't support simultaneous recording on multiple devices. But if you've got a bike computer then there's nothing to be gained by also recording on your watch, you won't get any more data.
There's another related defect if you use one of their chest straps that records and stores heart rate data for later download (this is mainly for swimming activities where radio can't be used). If you record an activity on your watch and it syncs to Garmin Connect before downloading heart rate data, then after the watch downloads from the chest strap it will create a duplicate activity in Garmin Connect instead of updating the existing activity. Customers have been complaining about this for years but Garmin doesn't care.
If it's pushed to Strava from another device (Garmin, Wahoo, etc) then you can download the original file, which will have all the data that the original device recorded. This may have auto pausing, may not.
On e.g. files that are uploaded from my Garmin watch, Strava adds its auto pause as a filter on top of the data: iff the original data doesn't have any pauses (Garmin auto pause not enabled on my runs), then Strava will cut out periods of time when you're standing still; otherwise it'll leave the data alone.
