Intercom integration with Joomla. Simple integration that just modifies the index.php of your current template. Add the following code at the bottom of your current index.php file

index.php

    <?php 
    ////////////////////////////////////////////////////////////////////////////////////////////////
    // Intercom integration
    ////////////////////////////////////////////////////////////////////////////////////////////////
    // - Supports logged out users / visitors
    // - Supports logged in users and has logout as well (NOTE: customise logout behaviour based on your theme)
    //----------------------------------------------------------------------------------------------
    // IMPORTANT
    // - Customise logout behaviour based on your theme (used "protostar" theme on a standard install of Joomla! 3.7.2 Stable [ Amani ] 22-May-2017 09:46 GMT as a test)
    // - Unsure how best to santize PHP code so using addslashes in this instance. Do comment if there is a better way (did not want to use htmlentities as would want to keep raw values)
    //----------------------------------------------------------------------------------------------
    // - Doc resources
    //    - Logged out snippet: https://docs.intercom.com/install-on-your-product-or-site/quick-install/install-intercom-on-your-website-for-logged-out-visitors
    //    - Logged in snippet: https://docs.intercom.io/install-on-your-product-or-site/install-intercom-on-your-web-app
    //    - Logging out: https://docs.intercom.com/faqs-and-troubleshooting/your-users-and-leads-data-in-intercom/how-do-i-end-a-session
    //    - Add any other custom attributes as you see fit https://docs.intercom.com/configure-intercom-for-your-product-or-site/customize-intercom-to-be-about-your-users/send-custom-user-attributes-to-intercom
    ////////////////////////////////////////////////////////////////////////////////////////////////
    
    $APP_ID = "YOUR_APP_ID";
    
    
    $user = JFactory::getUser();// get current logged in user details
    ?>
    <script>
      // logout of Intercom on logging out of Joomla: modify according to your theme
      jQuery(document).ready(function(){
        jQuery("body").on("click", ".logout button", function(){Intercom("shutdown"); });
      });
      
      <?php if ($user->guest) : ?>
       window.intercomSettings = {
         app_id: "<?php echo $APP_ID ?>"
       };
      <?php else : ?>
        // include user_hash attribute for identity verification https://docs.intercom.com/configure-intercom-for-your-product-or-site/staying-secure/enable-identity-verification-on-your-web-product
        window.intercomSettings = {
            app_id: "<?php echo $APP_ID ?>",
             email: "<?php echo addslashes($user->email) ?>",
           user_id: "<?php echo $user->id ?>",
         user_hash: "<?php echo hash_hmac('sha256', $user->id, 'YOUR_SECRET_KEY') ?>",
          username: "<?php echo addslashes($user->username) ?>",
              name: "<?php echo addslashes($user->name) ?>",
        created_at: <?php echo JHtml::_('date', $user->registerDate, 'U') ?>
        };   
      <?php endif; ?>
    
      (function(){var w=window;var ic=w.Intercom;if(typeof ic==="function")    {ic('reattach_activator');ic('update',intercomSettings);}else{var d=document;var i=function(){i.c(arguments)};i.q=[];i.c=function(args)   {i.q.push(args)};w.Intercom=i;function l(){var   s=d.createElement('script');s.type='text/javascript';s.async=true;s.src='https://widget.intercom.io/widget/<?php echo $APP_ID ?>';var x=d.getElementsByTagName('script')[0];x.parentNode.insertBefore(s,x);}if(w.attachEvent)   {w.attachEvent('onload',l);}else{w.addEventListener('load',l,false);}}})()
    </script>  
  </body>
</html>