An API for querying and managing digital products to facilitate in-app purchases from web applications, in conjunction with the Payment Request API (which is used to make the actual purchases). The API would be linked to a digital distribution service connected to via the user agent. In Chromium, this is specifically a web API wrapper around the Android Play Billing API.
This is needed so that web apps in the Play Store can accept purchases for digital goods. (Play policies prevent them from accepting payment via any other method.) Without this, websites that sell digital goods are not installable through the Play Store.
Docs: https://github.com/WICG/digital-goods/blob/master/explainer.md https://docs.google.com/document/d/1Jbt2Mzt-xg1cWVlFScBQsoX_pE8Kg1gYpulxUSV8FM0/edit
Explainers: https://github.com/WICG/digital-goods/blob/master/explainer.md