I have Airfoil control support working in SmartThings via the following small project to add a REST API to Airfoil: https://github.com/jnewland/airfoil-api
The SmartThings integration is app is a service manager / device type combo. Here’s how it looks:
Speakers are exposed as “dimmers” to SmartThings. On == Connect, and Off == Disconnect. SetLevel == Volume Control.
This app does not have the ability to stream music or play text, and it likely never will. It’s only utility is to control a running copy of Airfoil (similar to what you can do with Airfoil Remote) via SmartThings.
For those wanting text to speech, this could be combined with another similar app that runs on a local mac and proxies to the
say command, but that’s not what I’m personally working towards.