With this application you can calculate the amount of earnings that your YouTube channel can have with a certain number of reproductions.
For that, it's important to create an earning profile with the last month channel data (number of views, number of views not able to be paid, etc.), and when you have created a profile already, you only need to type the number of reproductions that you will to figure its profits and click on calculate it.
Any questions you have, there on the app you can found several "'?" icon's.. please click on them, there is an explanation of what are for every field.