Originally Posted by Mivo

Actually, this is an interesting point that I never thought about. This may apply to me, too. I haven't kept an eye on it , but it seems true that I get naturally sleepy when I'm reading on an e-ink device while a tablet keeps me awake, and I do fall asleep more often with the e-ink reader on my chest or next to my head. This doesn't happen with the tablet, though that's probably partly also because I know subconsciously that the reader can afford falling off the bed, while the tablet is more fragile.