Amazon’s new Underground app is coming to a host of new countries, including Italy, Spain, Ireland, Austria, Switzerland, and Belgium. In total the app will roll out to 16 new regions.

First launched in August of this year, the Amazon Underground app gives users free access to games and some in-app products that normally require a fee. In lieu of in-app sales, Amazon pays developers based on how many minutes a customer plays a game. Already people in the U.S., U.K., Germany, and France have access.

Amazon says its Underground app has $10,000 worth of apps and games like Office Suite Professional 8, Fruit Ninja, and Angry Birds Slingshot Stella.

As we noted earlier this year, Amazon Underground stands to change the way apps are monetized. Rather than relying on micropayments from in-app purchases, developers can get paid for how popular their app or game is with users.