Another thing that got me thinking about this was Jim Dalrymple's review of the Apple Watch.
The meat of the review is about how the watch helped him accomplish an astounding change in behavior. I think this is a great thing, and a perfect example of technology improving lives. I don't think these kinds of results are limited to the Apple Watch, or even Apple specifically, though - a Fitbit, Jawbone Up, or any one of a number of other trackers could do the same thing. In this scenario, the one that introduces the least friction is best.