See PS4's Remote Play in action with Killzone: Shadow Fall on Vita
Just how smooth is the PlayStation 4's Remote Play functionality? A new video, uploaded by YouTuber Steven ter Heide, clearly (well in 240p) shows off Killzone: Shadow Fall, a PlayStation 4 launch title, being played on the PlayStation Vita.
The gameplay appears to be very fluid with no noticeable lag between the console and the handheld.
Sony recently addressed Remote Play between the Vita and PS4 in a Ultimate PS4 FAQ, offering the following clarification as to how to enable the functionality:
For Remote Play to function over a wide area network, a robust and stable WiFi connection and broadband Internet connection is required, and the local area network where PS4 is connected must be configured to permit the PS Vita system to access PS4.
Remote Play between PS4 and PS Vita systems leverages Gaikai’s proprietary game streaming technology. PS4 supports this technology on a system level in order to reduce the burden for developers. All activities performed during Remote Play will occur on the PS4 system, such as purchasing add-ons, earning Trophies, and saving game progress.
While this would normally mean you'd need pretty solid internet for such stable gameplay, Sony's Shuhei Yoshida also confirmed that you don't necessarily need WiFi or internet for local Remote Play. The two devices should be able to communicate with each regardless of internet speed, similar to how two 3DS devices can locally communicate even if not connected to an internet.