I created a program on my website that autogenerates the code to run In App Purchases. Click Here, then choose "Game Maker IAP" in the options menu. Type the IAP information in the "IAP List" field. For example: Code: id0, Item 0 Title, Item 0 Description, 1.99 id1, Item 1 Title, Item 1 Description, 2.49 id2, Item 2 Title, Item 2 Description, 2.99 Then, click "Generate Code". It will generate the code to run when the app starts, the code to run in the IAP event, an array "purchases[n]" to check whether item n has been purchased, and a script that allows you to call "scriptName(n)" when you want to purchase item n.