Google Play Billing

Definition

Google Play Billing is the Android SDK that apps integrate to sell digital products and subscriptions through Google Play. It provides the client-side purchase flow — showing the price, handling payment, and returning a purchase token on success. The library itself does not verify purchases; that is the job of your server (calling the Google Play Developer API).

Google Play Billing Library version 7+ is the current generation, with improved subscription management APIs and a streamlined purchase flow. The library handles one-time products, subscriptions (with free trials, intro pricing, and upgrade/downgrade), and consumable in-app items. All purchases follow the same pattern: client library → purchase token → server verification → entitlement.

Examples

• An Android app launches the Google Play Billing flow for "Pro Monthly". The user pays, the library returns a purchase token. The app sends the token to the backend, which verifies it server-side.
• A subscription upgrade from monthly to annual: Google Play Billing handles the proration, and the server verifies the new purchase token to update the entitlement expiry.
• Tierux integrates with Google Play Billing via the verify endpoint — you send the purchase token, Tierux calls the Android Publisher API, and returns normalized entitlement state.