DjZoNe

This plugins main goal was to provide the ability to any of your registered users, to invite more people to the community.
Please notice, that this plugin totaly ignores whether the registration is enabled or disabled to your blog.
<a href="https://downloads.wordpress.org/plugin/invite-friends.0.3.zip" rel="nofollow ugc">Download now!</a>
<a href="http://invite-friends.dev.rain.hu/" rel="nofollow ugc">Support</a> | 
<a href="http://invite-friends.dev.rain.hu/faq/" rel="nofollow ugc">FAQ</a> | 
<a href="http://djz.hu" rel="nofollow ugc">Author</a> 
<a href="https://www.paypal.com/cgi-bin/webscr?cmd=_donations&business=djzone@cracker.hu&item_name=Invite%20Friends%20for%20Wordpress" rel="nofollow ugc">Donate</a>
Some functions:
<ul>
<li>invitation sending</li>
<li>invitation cards limit per site</li>
<li>after activation, the user is logged in automatically</li>
<li>after activation, the user can be redirected to a custom URL</li>
<li>activation screen is using the same styles as the login screen (if you have customized login screen it will affect the activation screen as well)</li>
<li>Dashboard for custom settings Plugins > Invite friends settings</li>
<li>i18n support (localized messages)</li>
</ul>

Invite Friends

This plugin give the ability to anyone how registered to your blog, to invite more people, even if the registration is closed.

Ironikus

This plugin extends the possibilities of WP Webhooks & Pro by integrating emails with an extended webhook functionality. 
For a full list of the features, please check down below:
<h4>Features</h4>
<ul>
<li>Fire a webhook once an email is sent</li>
<li>Send an email on your WordPress system via webhooks</li>
<li>Support for certain tags like CC, BCC, FROM, REPLY-TO and more</li>
<li>Support for attachments</li>
<li>Support for HTML content</li>
</ul>
<a href="https://wp-webhooks.com/" rel="nofollow ugc">See plugin web view</a>
<h4>For devs</h4>
Feel free to message us in case you want special features – We love to help!

WP Webhooks – Email integration

A WP Webhooks & Pro extension for integrating WordPress emails

Invite Friends vs WP Webhooks – Email integration