Originally Posted by 2millionquest

For the same reason that the rules in the U.S. are different than the rules at LHR, because they are different countries and different airport authorities.

But I think you're confusing apples (no pun intended ) and oranges here. You need to remove your iPad from your hand luggage at most European airports; despite what some have reported in this thread, you don't necessarily have to remove the iPad from its own individual case. As I mentioned upthread, I keep my iPad in a slim folder type case. I've never -- at any airport -- been asked to remove it from that case. However, I also then put the iPad and case inside a larger neoprene sleeve. I have been asked to remove it from the neoprene sleeve. It seems like as long as the screen is visible (as in your example), there isn't an issue. YMMV, of course.