title: SMS messaging using Twilio with SIP
body: <p>I'm trying to use Twilio to send and receive SMS on my iPhone. I've gotten inbound and outbound calling set up <a href="https://stackoverflow.com/questions/48346740/how-do-i-forward-a-twilio-number-to-a-voip-phone">following these instructions</a>. I'd like the equivalent instructions for SMS. I'm presently using <a href="https://www.zoiper.com/" rel="nofollow noreferrer">Zoiper</a> as a SIP client, but that's flexible.</p>
  
  <p>The phone number configuration page (from <a href="https://www.twilio.com/console/phone-numbers/" rel="nofollow noreferrer">here</a> click a phone number) has a section called "Messaging" which allows one to configure a TwiML bin. However, I haven't been able to find any documentation about how to configure SMS over SIP, let alone TwiML code.</p>