Call is ended. The end cause can be found using callEndCause() method in the call object. The event 'onCallEnded' will be called on transition to this CallState.

Call is established, during this phase the ringtone should not play and instead the stream referenced in incomingStream, in the call object, should be played in an audio element. The event 'onCallEstablished' will be called on transition to this CallState.

Call is initiating.

Call is progressing, during this state, you might want to play a ringtone. The event 'onCallProgressing' will be called on transition to this CallState.