How to check for an app purchase on the Play Store (versus checking in-app purchases)

The documentation at https://developer.android.com/google/play/billing/gp-purchase-status-api.html describes how to check in-app purchases and subscriptions. But it is unclear how to verify the purchase of the app itself.

Is there a programmatic way to achieve this? Preferred to associate yourself with the ID of the device from which the app was purchased?