OK, si we have "other apple", "other smartphone", "samsung", "other samsung" ...
Why not add a category "Other Alcatel" and "Nokia Lumias with blue borders" ... those with a red or yellow border belonging to the "Windows Phone 7 other" category ? This would have made it clearer to everybody now?
If you believe this chart, all the 6 month old iPhone 4s have already been replaced (on their way to the recycler) and all the iPhone 3G/S have already been recycled into electric cars.
Anyway, the only logical conclusion we can draw is that the iPhones are data hoggers unable to manage their bandwidth efficiently...