It was still free for me yesterday afternoon - US store for iPad, if that matters - but now it's saying $2.99. Apparently the original price was $4.99 - according to the thread title - so I guess it's still on sale.. just less of a sale?
Get this game, is fantastic: the mood, feeling, controls, story, puzzles, atmosphere, visual, sound... its all perfect and cant beat the price of free.
The Mac version is free as well (for the first time ever): https://itunes.apple.com/app/nightsky-hd/id523327074?mt=12
This is a fantastic physics based puzzle platformer with a great, moody atmosphere. One of those AppStore gems you just have to play. The only problem I had with it was battery drain on my iPhone 5. The phone is not jailbroken (I played the game on iOS 6.x.x months ago, I don't know how it performs on iOS 7). The game heated up the back of the device like the best looking games I played in the past (Unreal engine games, Real Racing 3 or Asphalt series), and with a simplistic, minimalist graphics it's obvious the game is just not optimized properly. Anyway, despite the problems I can highly recommend the game.