Vita can be used as a PS3 controller via Remote Play – Destructoid
As much as I loved remote play with the PS4, it would have been really cool at the time to have a fully developed remote play feature with the PS3. : r/ vita
How to Connect a PS Vita to a PlayStation 3: 3 Steps
What's everyone's thoughts on remote play : r/vita
Remote Play (Concept) - Giant Bomb
Remote Play with PS Vita on your PS3 - YouTube
Ico & Shadow of the Colossus Collection, God of War Collection PS3 get PS Vita Remote Play today - Gaming Age