The most infuriating device I own when it comes to this is my Kindle, I'll pull it out and start reading on the ground, I usually tuck it away under my arms on my lap when the attendants walk by to do their checks.

I've honestly debated explaining in detail how e-ink technology works to flight attendants because they can't grasp the idea that just because something is showing a picture doesn't mean it's consuming power.

To top it off... I don't think you can even power the damn thing off, screen saver mode, yes, wireless off, you bet, but when you flip the switch and a picture pops up to replace the words on the page the flight attendants stand there waiting for it to go blank.