Originally Posted by
wizard69 
Using your logic Apple should have never introduced the 11" AIR because they have the 13" model.
Apple should introduce a 9", 7", 5", 3", and 1" MacBook Air, then.
Now that you've read the above, I'm sure you've come to the conclusion that there IS a minimum usable size for any device type. For the MacBook, it's 11", as that's as small as it can be made without compromising the keyboard. For the iPad, Apple has said since the release of the iPad that 10" is the smallest the screen can be to deliver tablet software worth using. The public agrees.
Same with the iPhone. A 2.5" iPhone was "guaranteed" in 2008. Because we all know that the 3.5" screen was too big.