This build of Spidermonkey is used by the Mobile Couchbase project, so that we can run JavaScript in a background thread.
If we can figure out how to use the built-in JavaScript on iOS without blocking the UI thread, we'll use that instead.
For more about the constraints we are working within on iOS, and how to contribute to the project, see the readme's of these two projects:
Erlang for iOS: https://github.com/couchbaselabs/iErl14
CouchDB for iOS: https://github.com/couchbaselabs/iOS-Couchbase
To join the development effort, meet us in the Google Group for Mobile Couchbase