An in-app purchase is a transaction made from inside a mobile app to buy digital content or services, processed through the app store’s own payment system rather than the developer’s. The platform handles the checkout, charges the user’s existing account, and pays the developer their share. This made buying digital goods on a phone nearly frictionless, since the user does not have to enter card details for each app, and it became the core mechanism behind freemium apps and subscription services.
Apple exposes in-app purchases to developers through a framework called StoreKit. Apple’s developer materials describe the App Store as “a powerful commerce system” that handles “end-to-end payment processing” and supports building purchase flows “using StoreKit views,” noting that “with as little as one line of code, StoreKit views clearly present the description, price, and duration for each level of service.” The developer integrates StoreKit, defines the products, and the platform takes care of the actual money movement.
Apple defines several kinds of in-app purchase. As its documentation states, “you can offer one or more types of In-App Purchases: consumable, non-consumable, auto-renewable subscription, and non-renewing subscription.” Consumables are used up and bought again, such as game currency or extra lives. Non-consumables are permanent unlocks bought once. Auto-renewable subscriptions charge on a recurring schedule until cancelled, and non-renewing subscriptions grant access for a fixed period that the user must renew manually.
Google provides the equivalent on Android through Google Play’s billing system. Google’s documentation describes it as “a service that enables you to sell digital products and content in your Android app, whether you want to monetize through one-time purchases or offer subscriptions to your services.” It offers “a full set of APIs for integration with both your Android app and your server backend,” and like Apple’s system, it is restricted to digital items; Google notes that “for physical goods and services, or other non-digital content,” developers must use a different payment path.
The defining feature of these systems is that the platform is the merchant of record and takes a cut, historically 30 percent and later 15 percent for many smaller developers and longer subscriptions. The requirement to route digital purchases through the platform’s billing, and pay its commission, became one of the most contested aspects of the mobile ecosystem, since developers could not bypass the cut for digital goods sold inside their apps. That control over payments is what turned in-app purchase from a convenience into the financial backbone of the entire app economy.