Amazon has launched a new service Underground which offers consumers the chance to play "$10,000-worth" of selected Android apps for free. As it keeps reiterating - "actually free". This includes various well-known paid for apps and games, and In App Purchases for many more.
Observers who have tried the service have confirmed, even the priciest in app purchases can be made.
In return for the developer waiving their normal income stream from the sale of app or IAP, Amazon is paying out at a rate of $0.002 per minute the app is open and running in the foreground of the device.