But, keep in mind, iPhone apps are already expected to be at least somewhat flexible in height. Use a well-written app while you’re on a phone call or making a recording with the Voice Memos app, and you get a double-height status bar (green for phone calls, red for recordings). But the double-height status bar doesn’t cover the content of most apps. Springboard tightens the spacing between its rows of app icons. Apps like Mail, Safari, and Calendar move the top of the window — the UINavigationBar — down to account for the double-sized status bar. The same is true for third-party apps.
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What has occurred to me, though, is that Apple could, with the (presumed) upcoming WWDC introduction of iOS 6, further encourage developers to be flexible in this regard by changing the way notification banners are displayed. As it stands, notification banners are shown one at a time, and cover the content of the underlying app. WebOS seemed1 more elegant in this regard — WebOS notification banners stacked on screen, and the current app shrunk to fit the remaining space.
If Apple introduced something like this in iOS 6, they could encourage iOS developers to adopt the recommended APIs to be responsive to changes in available vertical screen space. For now, they could pitch this in the context of shrinking screen space in response to on-screen notification banners, but, come October, apps that do the right thing would automatically be responsive to, say, a new device with 176 more pixels.
