Screens are traditionally measured diagonally. This worked fine when everything was a 4:3 ratio. Now that ratios are more variable, but we still use that measurement. Microsoft's claim about the diagonal measurement is absolutely true; they never mentioned screen area. Apple was certainly happy to make the iPhone 5 screen taller and call it a brilliant, beautiful, amazing, really great, 4" screen.
I think what they say is shady, but as the parent of this thread states, it is technically accurate to say that their screen is larger by industry standard measurements (i.e. corner to corner).
But the way we measure the size of things is ... by their size. We could just as well say their statement is true if we agree to define "bigger" as "smaller" and vice-versa.
I'm definitely not defending microsoft here, because it's not something I understand the reasoning of. For some reason, we decide to measure monitors/tvs/displays by their diagonal. I don't get it, but that's what happens. When someone says '15 in screen' they mean 'a screen with a 15 in diagonal'.
When microsoft says 'it has a bigger screen' it is a shortcut to saying 'the ipad has a 9.7 in screen, and we have a 10.1 in screen. therefore ours is bigger.' Given the context of talking about screens, this does make sense.
You can point out that 'oh, but the ipad has a bigger screen by area' and you are correct. But that doesn't change the fact that the number associated with screensize for every fricken screen on sale today is bigger on their product than it is for the ipad. That's not a lie.
I wouldn't be surprised if they can legally say "The Asus tablet has a 10.1" screen and the iPad has a 9.7" screen", but I'd strongly expect they need a "* based on diagonal measurement" footnote to get away with calling that display "bigger". But I'm not a lawyer.
I think what you mean to say is "by their area" which is not necessarily true.
Sometimes, we do measure things by a single dimension. Such as height. A person can't claim a world record on hobese.
Area would probably be a more useful measurement for screens but historically, for better or worse, that's not they've been advertised and that's not how consumers are used to comparing them.
A person can't claim a world record on height by being morbidly obese.
Yeah, but a person could claim a world record on size by being morbidly obese. If they said "I'm the biggest person in the world", they'd be making a statement that can be reasonably judged technically true, even if the listener might mistake their meaning to be that they're the tallest. Anyway, I know what you mean, I just think this is past the line of being arguably "technically true".
All the laptops, tablets, TV screens I have seen are measured diagonally. That's how it's always been done. Maybe that's not how it should be done. But it IS how it's generally done.
And I've got no problem with them saying their diagonal is bigger. But, to me at least, they can't say the screen is bigger and be on the "OK" side of even technical truthfulness.
Could I also claim that a 12" by 1" touchscreen is bigger than a 10.1" since it has a 12.04" diagonal?