A couple of weeks ago Facebook shared a video with some behind the curtains details about the realisation of Paper, their iOS new fancy client.
Among the talks a bomb was released: they were going to open source their animation framework POP, and they finally did!
POP it has been released for iOS and OSX, it can animate everything, not only CGLayers, you can even animate volume or other object’s properties.
And to whet your appetite before heading to the repo check Codeplease’s posts on POP