conversations.js

var client = new Twilio.Conversations.Client('token');
var convo = client.conversation('myCall');

convo.display('#them', '#me').then(function() {
  console.log('now your local media is showing, as is theirs!');
}).catch(function(err) {
  console.log('oops, something bad happened')
});

convo.on('participantJoined', function(participant) {
  console.log(participant.name + ' just joined!');
});