I’m a keen swimmer and try to swim at least a mile every day.
I’m usually found at Pancras Square Leisure where they have a nice 25m pool.
I used to use a Swimovate Poolmate Pro HR watch tracked my strokes and laps and allowed me to upload all that to a computer to check my progress (or not).
I tried a Swimmo, but found it too bulky and clunky to use – and the lack of any buttons was a pain and made the whole UX horrible.
I now use an Apple Watch 2 which is much better and more comfortable that both the Poolmate Pro and the Swimmo.