I have a Garmin Forerunner 220. The Garmin app on the iphone s*cks. I mean it's pretty darn bad. Every so often I have to delete and reinstall it. It fails to send data to health about my runs. At least it uploads my run data to my coach and it never fails to do that so I can live with the fact that it's a poor app. Thanks to a poster earlier in this thread, I've downloaded Lark. I like it so far.
One note of caution to those considering Apple Watch as a fitness tracker. Despite the fact AW has more processing power and better sensors than just about anything from Fitbit, Polar or Garmin, the software just isn't ready for prime time for anything beyond "stand reminders" and walking. When I tried to use my AW for running, it was consistently off on distance by about 5%. At first, I thought this was due to the fact I wasn't properly running apexes on USATF certified running courses until I got my Garmin.
During a marathon, my Garmin recorded 26.2 miles for a 26.2 mile race. But my AW battery died and I never got the data. Well that's not entirely true. I got something like 60,000 steps. Steps? What runner cares only about steps? So when I run, I run two-wristed. I have a Garmin on my right wrist and the display shows nothing but distance, elapsed time and trailing pace. My Garmin's distance measurements are also perfect for half-marathons, 10Ks and 5Ks. What is 5% distance measurement error? It's the difference between qualifying for Boston (BQ) or not, that's what. My AW showed me an 8:30 pace for what was actually an 8:55.5 pace. My real pace was too slow for somebody in my age group to BQ. Meanwhile if I want to see what time it is or check for text messages from my significant other, my AW is on my other wrist but I never bother trying to get runmeter or any of the other so-called running apps started on my AW. I avoid them because it's always a hit-or-miss spinning-wheel laden frustrating waste of time I could spend simply running.
Don't get me wrong here. I'm not bashing AW. It's fine for what it is. Just don't get all bent out of shape when you find it isn't well suited for intermediate to advanced fitness tracking applications. Next time you see competitive runners in a video, glance at their wrists and every single one of them has something round with a plastic strap (Garmin, Polar, etc) and almost nobody is (yet) wearing an AW. If you are a competitive runner looking for pace, heart rate, long battery life, accurate GPS, and accurate steps based distance during GPS loss then buy a Garmin first. If you already have a Garmin, adding an AW will give you world class smart watch features, just don't make the mistake of leaving your Garmin at home if you are going out for a run.
As for what the OP said about saving $100. That makes AW a no-brainer for someone who doesn't have one yet. I'm sorry I missed out on that discounted price but I think it was well worth missing the $100 discount to be one of the first people to have an AW over 6 months ago. I pre-ordered a mere 3 hours after preordering went live and because I ordered the single most popular model, I still had to wait weeks for mine arrive. I've been thinking about getting a rose 38mm AW Sport with white band for my significant other. It would be great to pick up one for her at "only" $250 but I think it's too extravagant a gift at this stage in our relationship. Once again, timing is more important than saving $100. Perhaps we'll be at that point of commitment by the time AW2 comes out and I can order her one of those on its launch day.