Indeed. So is there any reason to assume that the page that my opponent is showing me on his tablet screen, after we've just stood around for 5 minutes waiting for the thing to boot up, is any less tampered with than the printout the guy at the next table has?
At least with a physical book it's a little harder to tamper with it convincingly. I'm not seeing any reason to trust a digital edition any more than a printout, though.