- This was a regression caused by the fix for issue #2933:

https://github.com/jquery/jquery-mobile/issues/2933
https://github.com/jquery/jquery-mobile/commit/1a5224047b9a0e1302923adc96f77238489c9da1

This triggered a bug on iPhone/iPod Touch devices running iOS 4.2 - 5.1 where the browser *ALWAYS* applies a landscape media query. This bug does not exist on iPad.

- Removed the use of the landscape media query, and switched to using window.innerWidth/innerHeight w ith a threshold to determine if the device is currently in landscape mode. A threshold is necessary because on small form factors like the iPhone, the user can enable the developer console which takes up more vertical space, making the useable width of the browser window larger than the height.