App Store Server API
The App Store Server API is the server-to-server REST API for managing App Store transactions — looking up transaction history, fetching all subscription statuses for a customer, requesting test notifications, and issuing refunds. It pairs with StoreKit on the device and with App Store Server Notifications v2 for asynchronous state changes. Authentication is JWT (ES256) signed with a key created in App Store Connect; payloads and responses are JWS-signed JSON.