I don't know of any research, but the issue is that it's too highly stimulating. Real life can't compete with carefully engineered intermittent dopamine rushes.

I don't know of any research, but the issue is that it's too highly stimulating. Real life can't compete with carefully engineered intermittent dopamine rushes. So you end up with fidgety kids who are uncomfortable unless they're getting some sort of "fix". It's a silent epidemic. Some years ago I went hitchhiking through Iceland. Gorgeous country. Of all the cars I rode in, maybe half a dozen had children. In every instance - EVERY single instance - the child had an iPad or phone, and was playing with that instead of admiring some of the most beautiful scenery in the world.