The IB attempts to offer best case senario but it does not represent
the correct screen location. If you have a navigation view or tab view
then these will affect the placement of the objects in your nib. The
best way is to either know the exact height of the parent controller
object (like the navigation bar or tab bar) and adjust the controls in
the nib accordingly. It looks wonky in IB but works fine when you run
the program. IB attempted to put placeholders there to help with this
but they screwed up the implementation as far as I can tell. I remove
all the guides and manually place the objects. It leaves empty space
where the guides used to be.
Hope that helps. Maybe someone can better explain the IB
implementation of guides better.