Amazon announced plans to make their Appstore available to developers in the U.K., France, Spain, Italy and Germany this summer. The branch of the popular online retailer has seen a boost from free demo function and one-click purchasing.

“We are thrilled at the success our developers have experienced on the Amazon platform in the last year,” said Amazon Appstore vice president Jim Adkins. “Some developers have seen revenue double since the launch of In-App Purchasing. We’re excited to open the door to even more opportunity by expanding app sales outside the U.S. “We see tremendous potential for current developers in our distribution program to grow with the international expansion. We also encourage new developers to join and participate in the platform’s growth.”