SharePlay will be compatible with all DualShcok 4 PS4 titles and does not require special coding from developers.
The function, arriving as part of an upcoming PS4 update, allows players to have their friends take control of their game over the internet using PSN’s new streaming technology.
Think of it as an invitation based Remote Play.
“For example, say, a friend has a game that I don't,” Sony Studios boss Shuhei Yoshida told Famitsu, as reported by Kotaku. “I ask them to let me play it, and if they send me an invitation, I can access their PS4 and play while watching the video that is streamed.
"You can save your save data to your own account*, so if you like a game you played via SharePlay, you can buy it for yourself and continue where you left off. Or, if you get stuck in a game, or there's an enemy or stage you find difficult, you could hand over the reins to a friend for those areas."
SharePlay will work with all PS4 games aside from those that require the PlayStation Camera.
*UPDATE: Sony has contacted MCV to clarify some details about game save data.
"The original interview was slightly incorrect, probably misunderstood Shuhei's explanation," a rep told us. "In Share Play, the visitor (the one who doesn’t own the game) takes over the host's (the one who owns the game) account, so the visitor cannot save their play data onto their own account."