While the majority of app markets have already adopted this digital scheme, Amazon has just today announced the open availability of their in-app purchasing API. The in-app purchasing API will allow developers to offer digital content to its users in the form of microstransactions. Content such as expansion packs, weapon upgrades, etc. become available to purchase from within the app and usually cost less than a dollar. This monetization model has gained much traction as of late and while the majority of developers implement it in a morally acceptable manner, others simply try to nickel-and-dime users by making their apps virtually useless unless you pony up for the additional content.