If you need your participants to access the game by scanning a QR code, all you have to do is generate one and put it into your Leaderboard.
Generating a QR Code
Click the Game Links button
Clkick the Generate QR Code button
Save the QR code to your computer
Adding the QR Code to your Leaderboard
Once you have a QR Code, navigate to Trivia > Edit > Theme
Click on the Edit button under the Leaderboard thumbnail
Click on the Choose File button under Logo and browse your computer for the QR Code to upload it. Then click on Update
By default, your QR Code will be placed on the top-right side of the Leaderboard. You can change this by changing the Top and Left alignment values.