I really like the overall result of Persona when used for logging into a web site, but has anyone come up with a good way of integrating Persona login with mobile apps or APIs?

I suppose mobile apps would ideally use some sort of Persona login service provided by the underlying OS, and until such a thing exists I guess an app could reimplement all the user-agent logic and load the user's login page in a webview. But I have no idea how at all I would go about designing an API for a website which uses Persona for logins.