This is the Amazon GameOn extension and Demo project. With this you can access the Amazon GameOn API, permitting you to create tournaments for your players as well as award them prizes for participating.
There are a number of https://help.yoyogames.com articles outlining how to use Game On and set up leaderboards, etc., and the extension comes with a PDF manual included which explains how to use the demo and lists all the scripts and objects required to use the GameOn API.
For more information on GameOn see the following articles:
Version 1.1.1. Published January 21, 2019
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