In the Quadris game you need to place 4-cell blocks side by side to fill up the lines like everyone did in the Tetris game. There are some key differences there: you cannot rotate the blocks and you can place it anywhere on the field (not just on its bottom). The filled lines disappear and you get some bonus points. By removing several lines at once you can earn even more bonus points. Also you can place the current block to the hold zone on the left top corner of the window to use it later – just tap to the current block inside the frame. Tap it again to retrieve a block from the hold zone. To place a block on the field you just need to tap a cell which should get the top left cell of the current block. Or you can drag it anywhere inside the field and put it there.