itthinx

Activate and the Captcha will appear on the affiliate registration form when the <a href="https://wordpress.org/plugins/captcha/" rel="ugc">Captcha</a> plugin is activated.
Requirements:
<ul>
<li><a href="https://wordpress.org/plugins/affiliates/" rel="ugc">Affiliates</a> or <a href="http://www.itthinx.com/shop/affiliates-pro/" rel="nofollow ugc">Affiliates Pro</a> or <a href="http://www.itthinx.com/shop/affiliates-enterprise/" rel="nofollow ugc">Affiliates Enterprise</a></li>
<li><a href="https://wordpress.org/plugins/captcha/" rel="ugc">Captcha</a></li>
</ul>

Affiliates Captcha

Affiliates, Affiliates Pro and Affiliates Enterprise integration with the Captcha plugin.

shalior

WP Referral Code is a WordPress plugin that helps you generate a unique referral code for each of your users, enabling you to start your own version of referral marketing. Upon user registration, the plugin captures the refer code automatically. Additionally, WP Referral Code provides a user-friendly “copy refer link box” that allows users to easily copy and share their referral link.
This plugin is dependent only on the WordPress core and can be used with all other plugins. However, the logic after successful referral registration is up to you. To help with this, two important hooks are provided. For more information on how to use them, please refer to the plugin documentation, which can be found on the plugin website <a href="http://shalior.ir/wp-referral-code" title="Shalior" rel="nofollow ugc">Documentation</a>.
Several shortcodes are available to help you place things where they need to be. A list of these shortcodes can be found in the plugin options.
All information related to the referral status of a user can be found on the user edit page (Dashboard->Users->select a user). Here, you can view how many users the user has invited and who they were referred by.

WP Referral Code

This plugin brings referral marketing to your WordPress website. It's dead simple, fast, customizable, and it's all free!

Affiliates Captcha vs WP Referral Code