If an end-user re-installs your app on the same device, or deletes the device's local storage so that the locally-stored License Key is unavailable, the License Get request will either return the License Key last used on that device (if "Device Recovery" is enabled for that app), or it will issue a new License Key (if "Device Recovery" is disabled for that app).

By this means, if "Device Recovery" is enabled for an app, your end-users will not lose any in-app credits they previously had. If "Device Recovery" is disabled, your end-users will permanently lose any credits they previously had unless they remember their previous License Key and you provide a way for them to change their License Key within your app. According to the app stores, if an end-user has permanently lost credits that were related to an in-app purchase, you are under no obligation to provide a way of "restoring" them, since customers "know and expect that they are consumable".