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Either one should do great for that, but I would read the reviews carefully. Most swim trackers seem to do freestyle well. But, breast stroke has given some trouble.
Just ordered the FitBit Flex 2. I'll give a shot. If provides me the basic swimming info (laps/distance/time/calories) accurately, that will be enough for me to pass the AW2. For $100 sounds great and I can keep using my Omega Seamaster.
 
Can anyone who wears both the Apple Watch and Fitbit comment on how similar or different the step count is between the two? I used to wear the Fitbit before I had the Apple Watch and for the same activities, Fitbit always seemed to give me more steps than the watch.

Apple Watch is always lower for me, but not by a significant amount, currently on 6990 on the Fitbit and 6658 on the watch (desk sit down day in an office a 2hr drive from home = bad day!). Bearing in mind I sleep with the Fitbit on and half the time in the morning will wander round with that on before putting my watch on, they are about the same.
 
My experience with Fitbit is that the One is super-accurate (I've counted 1000 steps a few times and it's right to within a few steps) but the wrist worn ones aren't (I've had three - they break quickly - and all have wildly over counted steps if I do any task involving the slightest arm movement; one of them offset the overcounting by refusing to count at all if I wore a coat).

I wear a One as well as my Apple Watch because I like the challenges on Fitbit. The step counts are usually pretty close so my view is that the watch is hugely more accurate than the wrist-worn Fitbits.
 
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