This is a 3d version of the classic Minesweeper game, where you have to clear the grid without hitting any mines. You can choose to play on your own or online against another player to see who can complete the grid first.
To start playing the game you need to touch a square on the grid. If a number is shown then this is to tell you how many mines are surrounding that square. You need to use the numbers to help you decide which squares are clear and which ones have mines. To place a flag on a square that you think has a mine, press the button in the top right corner of the screen to activate it. Now click on the square and a flag will be placed. To complete the game you need to find all of the squares that are clear.