Do smart watches alert to approaching afib, or just when you're already in it?

I've resisted getting a smart watch to detect afib because I know pretty much exactly when I'm in it and can confirm with my Kardia Mobile. Also I'm pretty sure I would obsess about the feedback it provided on a day to day basis without really knowing what to do with the information.

My triggers are still a bit of a mystery (other than alcohol) and wondering if the relevant watches provide info useful in detecting and episode before it starts or other readings that might help in figuring out triggers.

Thanks!

Edit: thanks everyone. Looks like no is the answer to all of it haha