The trick here is the z-index.
You have a view that the user is viewing (View A). Behind that could be another view that's waiting to be revealed (View B). Clicking a button on View A, or perhaps swiping across View A, would cause it to animate to the right -- revealing View B waiting below. Finish your work with View B, then you slide View A back in to place.
This same idea could be used to review multiple levels of views. View B could slide to reveal View C, and so on.