Danilo Campos, iOS developer for Hipmunk: "The conjecture I'm buying, because it feels most consistent with Apple's priorities, is that the screen width and horizontal resolution will remain the same – but the screen height and vertical resolution will scale upward to hit the 4 inch mark. If Apple does this, it's actually pretty great news. The user gets to see more content at once. Auto-scaling height this way is already supported by Apple's layout tools. There's a decent chunk of apps, if they set their auto resizing masks properly, where developers wouldn't even have to change anything to support a taller display. So, if this happens – and it seems like the most Apple-y outcome I'd imagine – I'm losing zero sleep. If they alter the screen resolution in multiple dimensions, well, then things get a bit more complicated."
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