All iOS apps require a splash image (otherwise it's just a black screen while it spins up), but Apple strongly discourages using actual splash screens for this purpose: it's a very jarring experience, and also magnifies the apparent time between launch and ready states.
Instead the official recommendation is to make the splash image a stripped down version of your app's home screen - for an address book, this would be the main screen without any data, for example. This gives the app a more immediate feel, and also effectively hides a lot of the load time, since there is also no visible transition between the loading and ready states.
Of course, this is far from the reality of things - a lot of apps use splash screens for a variety of reasons, and most do not gracefully transition between splash and ready states (e.g., that empty address book splash screenshot will just magically pop into a ready view, instead of animating into said state).
Instead the official recommendation is to make the splash image a stripped down version of your app's home screen - for an address book, this would be the main screen without any data, for example. This gives the app a more immediate feel, and also effectively hides a lot of the load time, since there is also no visible transition between the loading and ready states.
Of course, this is far from the reality of things - a lot of apps use splash screens for a variety of reasons, and most do not gracefully transition between splash and ready states (e.g., that empty address book splash screenshot will just magically pop into a ready view, instead of animating into said state).