This could one day be useful, but if you spend too much time looking at the screen of your watch, you won't execute the drill properly. (t3.com)
I will personally still prefer actual books over ebooks, because I enjoy not staring at a screen for at least a small portion of my day. (creativecontentcoaching.com)
Other reports indicate that it could be as much as 11 hours each day that the average American adult spends looking at a screen of some kind — including mobile devices like phones. (mindbodygreen.com)