Actually, both the OS X and iOS calendars do support flipping between months with a swipe. Arguably, the leather effect at the top aids in this by reinforcing t

Actually, both the OS X and iOS calendars do support flipping between months with a swipe. Arguably, the leather effect at the top aids in this by reinforcing the physical-analog affordance, though the torn edges are a bit much. Now the address book, that's a nearly perfect counterexample. Once again, on both iOS and OS X, it has "pages" that invite a swipe – except here, swiping does nothing. A dead affordance that only serves to frustrate and confuse the user.