I have created a Monopoly Hamburg game board, on which are various famous Hamburg streets. You can see the QR-Codes under below the street names. When you want to buy a street, you have to scan the QR code and it will be added to your collection. Now when someone else enters the street, I can look up on my phone how much rent needs to be paid. There are 2 versions of the game. The first version is finished and wont be developed any more. The second version is still in development. When a QR code is scanned, a cookie is set. When the script detects that a cookie with the name of the street is created, it changes from dispolay: none; to display: block;. Briefly the street is displayed. When you want to quit the game, you scan a certain QR code and the cookies are removed. V2 is still in development and works a bit different. At the beginning it is checked if you have already selected one of 6 players. If not, you will be redirected to a page where the player and player name will be selected. This information is stored in a database. In addition, the information that you have $1500 is automatically added. If you now want to buy a street, you scan the respective QR code. The current account balance will be shown and you will be asked if you want to buy the street. If you buy the road, the price of the road will be deducted from the account balance and the owner will be updated in a table. If the owner now scans the street again he can sell the street, mortgage it, build houses and hotels or go back to the overview. If someone else comes to the street they will be asked if they want to pay the rent. It is then automatically set the correct price. (With houses and hotel included.) With PHP I connect to a MySQL database and query the data.