What I'm basically doing is presenting a UIActionSheet using showFromBarButtonItem from a UIBarButtonItem in a UINavigationBar in an iPad app. What this does is present the UIActionSheet in a popover, which is what I wanted.
What I would like to do is change the background color of said popover from the default blue to one of my own. Is there a simple app store safe way to accomplish this short of rolling my own custom UIActionSheet in a popover solution?
Not really, because you don't get official access to any parts of the underlying UIPopoverController or its content view controller, let alone the view. On the other hand, as you imply, constructing your own view controller and view is pretty trivial.