Say what you want to say about the PlayStation Vita but it sure has at least one use, Remote Play. Sony has been pushing Remote Play with all of its PlayStation 4 games so far, including: Assassin’s Creed IV, Need for Speed Rivals and Battlefield 4, all of which work perfectly fine with the PlayStation Vita.
The only flaw with the Vita Remote Play seems to be that most of the games don’t have custom button mapping on the Vita, because the games don’t detect whether they are being used with a normal controller or with Remote Play. The only way to change the mapping would be to do it whenever you are enabling Remote Play.
Certain games, like Call of Duty Ghosts, do have custom layout options for Remote Play and defers when it is being used rather than the PlayStation 4 controller. Though the games that have this feature aren’t big in number, I am hoping that they do develop it for all the games that support Remote Play as it would be very useful.