Facebook Credits API vs Payvement

Can someone explain to me the difference between the Facebook Credits API and Payvement? Is Payvement simply an app that wra开发者_开发技巧ps the Credits API?

I'm basically looking for best practices for how to accept payments through a Facebook app and the water in the FB dev docs is very muddy and unclear. Thanks for any input!

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It looks like Payvement is geared towards the sale of physical goods, which you can't do with Facebook credits. Facebook Credits can only be used to sell virtual goods. It doesn't look like Payvement handles Facebook Credits at all, actually, and rather than being an API, Payvement is an e-commerce solution for the Facebook canvas.