The laptop policy from Shriram Krishnamurthi's "Accelerated Introduction to Computer Science" class is an interesting collection of resources on laptop usage in class.
I've definitely found that it is true that longhand note taking improves my retention and focus while device usage immediately kills it. The point about device usage distracting other people around you is particularly interesting though.
I feel like imposing this sort of rule is a deeply unpopular move in my social group, but I think they're mostly wrong about that. OTOH this is very much a question of competing access needs and I'm not sure what the best way to resolve it is.`