dismissing modalViewController all view move up by 20px

could you post some code?

 

I've seen this happen. Google for this problem and you'll see the solution. It happens when you directly add a subview to the main window, and then add a subview to the subview (if that made any sense), instead of using some sort of navigation controller.

The solution basically comes down to a hack. In the viewDidLoad or viewDidAppear controllers for your subviews you have to manually shift the whole view by 20px every time they display.