cubefeed

The problem: SMTP email delivery by some hosting providers can be extremely slow. This plugin reconfigures the wp_mail() function to send email using HTTPS (via Elasticemail API) instead of SMTP and creates an options page that allows you to specify various options.
Plugin Settings Options:
<ul>
<li>Enable or Disable Plugin.</li>
<li>Elasticemail API username</li>
<li>Elasticemail assigned API Key</li>
<li>Elasticemail REST API URL</li>
<li>Your account channel variable(optional)</li>
</ul>

ElasticEmail Plugin

Reconfigures the wp_mail() function to send email using HTTPS (via Elasticemail) instead of SMTP and creates an options page to manage the settings.

David Cramer

Caldera SMTP Mailer is not groundbreaking in any way. There are many SMTP plugins around some good some not so good. This is just to take away all the mystery with a to-the-point solution for configuring wp_mail ( and in turn phpmailer ) to send through SMTP over standard phpmail.

Caldera SMTP Mailer

Just what I needed to test on my local machine where php_mailer fails

ElasticEmail Plugin vs Caldera SMTP Mailer