I'm 50/50 on Ant+. My Garmin wearable does Bluetooth, which any Apple product does. There are a lot of bike computers that do both, so your cadence sensor or whatever talks to your computer, then you offload it from there to your desktop. A perfect solution? Meh, but it's not a difficult one. I mainly run, and ride for recovery, so Ant+ isn't as much of a priority. (And I don't know anyone making Bluetooth or Ant+ enabled running shoes. :D )

I app the hell out of my runs and rides, and yeah, I'll use my phone for that, because for some reason, Apple hasn't figured out that battery life is A Thing for many users. (I have no idea why they think it's a sports watch when there are much more capable performers out there.) My phone can manage a 2 hour run with ease while running GPS and Bluetooth, which is fine for me.

I run the same course 3x/week so I have dozens upon dozens of samples, and both the Garmin GPS and the Apple GPS seem to produce (in aggregate) results that are consistent within about 0.01 of a mile. That's around 52.8 feet, which, on a 10k distance, that's peanuts. You can count on greater variation from crossing over to this side of the street or that, or maybe taking a long curve tighter or wider. I think the technology is starting to reach maturity.