When you set up Rotate On, it asks which wrist and inside or outside. This would imply that it then knows which rotational direction should activate the screen. Not so. Yes, when I rotate my wrist up (I wear it on the inside) it turns on, but, if the screen then goes off and I rotate my wrist down, it turns on, again. So, from my basic experiment, it appears that it ignores the setting and just recognises rotation.