Tirwik it's a puzzle game in which you have to form color lines using boxes that change color every time you select a line. This boxes are set in a 5x5 board and change from red to yellow, to green and then back to red. You have 3 different game modes: Normal (get as much points as you can before your turns run out), Endless (play against your patience and get as much points as you can) or Board (try to set all the squares one same color in as few turns as you can).
To change the color of a specific square you need to click on 1 of the two buttons out side the board that are aligned with the square. This will make them the hole line of squares to change their color. You'll get points for each line you make. If you manage to make more than one line at the same time, you earn special bonuses and medals.