Does this API only support payments from a buyer to the merchant and nothing else? It seems that this in-app purchase API has no support for programmatically handling refunds and cancellations.. I love the embedded experience, but I need a slightly more robust API to work with..
Looking at the Google Checkout API, it's clear that this allows order refunds programatically. However, it also looks that the merchantID (basically the API key) is not usable between Google Wallet for Digital Goods and Google Wallet for Checkout.
Can Google Wallet for Digital Goods support programmatic refunds, and if not, can you still use the Digital Goods embedded payment experience with the Checkout API?