The tabstrip moving to the top is part of our adaptive rendering - as android apps tend to put it at the top. Its height may also change (you can change it via CSS, too)
I tried to reproduce the white area you describe in the Android 4.0.3 emulator, to no avail. The application does not add horizontal scrolling, too. See attached screenshot from our demos.
Perhaps the problem is phonegap specific? Is it possible for you to provide a sample project, where we can reproduce it?
All the best,
the Telerik team
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