If you wish to leave a game, you can press the door icon in the bottom left corner of the screen. Leaving a game will result in loss of XP and Coins.

Keep in mind that Klaverjassen is a team based game and that leaving will replace you with a robot. This forces your teammate to continue on alone, assisted by a robot.

The game also uses a leave game percentage, which will go up once a player leaves a game. The percentage is visible to other player.