iOS development: GameCenter and In-App activated default So I've created an application in XCode and I've tried to put it in the store.
However, the options In-App purchases and GameCenter are activated and I cannot uncheck them.

Why are these on? And why can't I turn them off? I don't see why they should be active as my application has neither one of these.

Thanks in advance
You cannot deselect them. As apple mentions here they are automatically added to explicit app ids. The only way to do not have them is to create a wildcard app id (which is not a solution in most cases as it has many drawbacks). 

Think of them as libraries added to your app. You do not have to use them and they change nothing to your project or to the way your app appears in the app store (unless you use them of course).