Updated on November 6th, at 14:50: Curiosity is now available on Google Play, too. It'll work on pretty much any device on Android 2.3 and up, says developer 22Cans.
You might also notice some general network issues on the iOS version, due to server overload.
22Cans programmer Richard Fabian tweeted, "can't decide whether I'm happy that people are playing, or sad that they are crushing our servers".
A little earlier than expected, Curiosity - what's inside the cube, the first game from Peter Molyneux's indie studio 22Cans, is now live on the App Store.
The free app presents you with an enormous cube, suspended in mid-air in a plain white room. Zoom in, and you'll find that the black monolith is made up of millions of tiny "cubelets" which you can break with a tap.
The goal is to break into the impenetrable box, cubelet after cubelet, layer after layer. You'll be working alongside every other Curiosity player in the world, co-operatively trying to unearth whatever secretive thing is located at the very centre.
22Cans explains that "the person who removes the last cubelet on the final layer is the winner and will automatically be sent a video link on their device explaining what is at the centre of the cube."
What's in the box?!
That person - and only that person - will see the contents. And it's something that the studio describes as "life-changingly amazing".
"The winner is free to do what they wish with the video link information - they can disseminate the link via social media or keep the content to themselves." However, the rules state that the winner is not allowed to sell the secret for personal gain.
You'll earn coins as you tap (and more if you master the subtle combo mechanics), and you can spend this currency on destructive items like firecrackers, bombs, and chisels, all of which help you crack open the cube at a faster pace. More items are marked as "coming soon".
Presumably, you'll be able to buy coins with in-app purchases at some stage - or how else will you afford the three billion coin diamond chisel? Molyneux previously said that this über-empowering master of destruction would set you back $50,000.
Right now, people are using the cube as an artistic canvas, and scribbling words and pictures into the first layer's face. It's actually more fun to look for interesting drawings than to tap away at the cube.
22Cans says, though: "Don't assume that the journey to the centre of the cube is simply tapping."
The game (well, 22Cans prefers to call it an "experiment") is out now as a Universal app for iPhone and iPad for free. An Android version should be on the way very soon.
This is, by the way, the first of 22 'experiments' that the studio will be producing, in the lead up to one final game. "Everything that we do, every thought that we have, every moment of a day, is all working towards this full game," Molyneux told VG247.