Wolfenstein: The New Order Takes Advantage of The PS Vita Second Screen Feature
While remote play between the PS4 and PS Vita is practically a standard console feature, the PS Vita also has the ability to act as a second screen, something that only a few PS4 titles uses. Wolfenstein happens to be one of those titles.
Found by accident, the feature allows you to view the games HUD from the portable device, along with the current level map.
Source: reddit