I would reall love to have an open source watch, but unfortunately both the pinetime and bangle.js 2 lack severely in the activity tracking, which is the primary reason for me to have a smart watch.

I'm not sure how the screen is on the pinetime, but on the bangle.js 2 it's surprisingly bad. Not a deal breaker by itself, but combined with a sort of limping experience on other parts, it's not a good product (yet).