Adding in-app purchase to originally free Mac app?

I would like to release a Mac app through the Mac App Store that is free.

However, I would like to add new functionality in a future software update that is enabled through an in-app purchase.

I reviewed the App Store Review Guidelines, and I did not see any prohibitions to this approach (initially free, later add new functionality enabled by an in-app purchase).

If anyone knows of any rules or policies that I missed that would prohibit this, I would appreciate a heads up on it.

Thanks!

As long as your application already has a functional ability for those who use it with free of charge, I don't see a problem.

Adding in-app purchase to originally free Mac app?
 
 
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