Glad I didn't depend on the Apple Watch's fitness and activity trackers being anything more than a gimmick - plan on wearing my fitbit Charge HR on my other arm when I get my Apple Watch. Should have known this was a gimmick just like Apple's Health app that includes next to no actual practical fitness tracking functionality
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You'd notice if you walked 3 miles through the day, it's not like it's just a casual amount of walking.
Sure it is; on days when I don't do exercise, I still cover over 3 miles over the course of a day, walking from the station to work, around the halls etc; and I have a desk job. 3 miles in a day is not much of a target.