Yesterday, Twilio introduced a new feature, call queuing.
This allows you to answer a phone call and place the caller into a queue. You can still use all the other Twilio features, like giving the person a message, and playing “on hold” music the same way you would for a Conference call. The API exposes information like the caller’s position in the queue, the time that the caller has been in the queue, the average queue time, and the current queue size. You can also capture events like caller hangups.
Today I have updated the twilio4j java library (version 1.0.4) to support these new <Queue>, <Enqueue>, and <Leave> noun/verbs.