[UIView transitionFromView:self.view toView:overlayView duration:1 options:UIViewAnimationOptionTransitionCurlUp completion:nil];
Will do the animation of the page curl up if thats what you mean. I haven't found a way to pause it half way like the google maps app does, but in theory if you implement the UIView animation delegate methods you might be able to pause it half way or something.
EDIT:
[UIView transitionFromView:overlayView toView:self.view duration:1 options:UIViewAnimationOptionTransitionCurlDown completion:nil];
is the curl down implementation of it.
Just so you are aware overlayView is UIView, not a UIViewController, not that it should matter but thats how I implemented it.