Come May, Kindle Fires users will have lots of free virtual coins to spend on their favorite apps. Announced on Tuesday, Amazon Coins is a new type of virtual currency developed by the retail giant. Users will be able to grab the new coins to purchase Kindle Fire games, apps, and in-app items from the Amazon Appstore. To kick off the new currency in May, Amazon said it will offer shoppers tens of millions of dollars of free Amazon Coins to spend on Kindle Fire apps. The company will also let customers buy more coins directly through their Amazon accounts. Amazon sees the currency as a boon for developers, as it will offer users an easy way to spend money on apps and in-app purchases. Developers will also get their standard 70 percent revenue cut.