Ask HN: Which is the most customizable/programmable smart watch?

There was one smartwatch prototype released by Jolla, maker of Sailfish OS. But sadly, it didn't see the light. Try contacting the founders.

Thanks!

So far, I've found this, but it doesn't seem to be programmable, in a conventional way:

I'll have a look at the Jolla prototype, and try to contact their engineering team, if it turns out to be relevant enough.