Considering you configured your VoIP Drupal with one of the providers, here is the sample code snippet that sends "Hello world" SMS:

<?php
$number = '+1234567890123'; //Number to send SMS to. Must be in E.164 format.
$call = new VoipCall();
$call->setDestNumber($number);
$text = 'Hello from VoIP Drupal';
voip_text($text, $call);
?>

Pretty cool, right?

Last week I held a session in Drupal Balkan Summit about VoIP Drupal and building SMS service using any local phone number.

In the video below you can see how to use Envaya SMS with VoIP Drupal in order to build SMS service which can receive and send text SMS messages using your local SIM number.