American developer Semi Secret is celebrating the spring bank holiday by making its punishing indie iOS game Gravity Hook HD free this weekend.

The game, which involves swinging between grapple points while trying to keep a rope taut, pits you against that most mighty of invisible foes: gravity.

We gave it an utterly creditable Pocket Gamer Bronze Award. "A uniquely punishing brand of gameplay," we said, "that slaps you away with its difficulty, but reels you back in with a fine presentation and excellent unlockable mode."

Grapple it up while it's still swinging free on the App Store.