Amazon will extend its in-app purchasing system, already available for the Kindle Fire or other Android devices, to games for the Mac, PC, and web. The move will allow game developers on those platforms to use Amazon's service, potentially broadening its revenue — the service allows users to make in-app purchases using credit cards and virtual Amazon currency. Amazon takes a 30 percent cut of revenue from each purchase: the same amount it takes from full app sales, and the same rate that Google charges developers for Google Play apps.

Amazon says it will help developers with discovery and marketing by making all in-app items automatically available on Amazon.com. It will also allow in-app purchases to show up on best seller lists and other recommendation services. "We're passionate about making game developers successful, and we'll continue to build services that make monetization easier and remove undifferentiated heavy lifting from developers," Amazon Games Director Mike Frazzini said in a press statement. The service is available for developers starting today.