In the week that I used both (before abandoning my Fitbit Flex), the Google
Fit app on my Android phone was more accurate for exercise-related steps,
and more self-consistent.
For example, the Flex recorded 2195 steps and 3126 steps, respectively, for
the exact same brisk-walking route two days in a row. The GFit app recorded
3994 and 3766. The route in question is 3.5 km and my brisk-walking stride
length is about 0.9 m, so the GFit numbers seem more accurate (and more
self-consistent).
That said, this isn't a huge, pressing "want" for me; I'm okay with
manually entering the GFit numbers once a day—in fact, I may prefer it,
since that way I can still accurately update my Beeminder graph if I forget
my phone or it dies on me and I keep track some other way.
Best regards, Met vriendelijke groet,
Grayson Morris
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