Septembers list of free games for PlayStation Plus members is now out. There is a few smaller games with cross buy. Which is good. Then there a few bigger games as well as a critically acclaimed one. You can read the official blog post > here. These games will be downloadable September 6, 2016.
PS4
Journey. This was first one PS3 back in 2012. Received a lot of rewards that year. Heard lots of great things about it.
Lords of the Fallen. Looks like of of those Dark Souls type game.
Badland. This is a side-scroller platformer. Similar to Limbo.
PS3
Prince of Persia: The Forgotten Sands. The 2010 version of the game.
Datura. A very interesting first person exploration/adventure game.
Vita
Amnesia: Memories. From what I have read it is a Japanese visual novel.