I'm starting to wonder what games will look like on smart watches. On phones, we got things like Angry Birds, although now there are a lot more desktop-like games for phones just because the power has increased so much. Smart watches will increase in power, but the size of the watch is likely to remain a very tiny touch target. "Idle games" might be a viable option, since they require little to no interaction, and it's possible that the ready accessibility of the watch screen could result in more "running around" games that only require occasional screen interaction. If your game is heavy on touch interaction, on the small screen, that is going to prove both difficult to use (because precise touch is difficult on such a small target) and no fun (because half the time your finger would get in the way).
You know what might work? Sliding puzzles where an edge-to-edge swipe now and then works well, or possibly slow card games, whether played online or against the watch.
Mokalus of Borg
PS - Something you can look at for a few seconds, then put down for an hour.
PPS - Someone will do it right, I'm sure.