AffiliateWP is an easy-to-use, reliable WordPress plugin that gives you the affiliate marketing tools you need to grow your business and make more money https://affiliatewp.com/
iDevAffiliate is standalone affiliate tracking software touted as the most feature rich, easy-to-use product in its class.
Affiliate Royale is a complete Affiliate Program plugin for WordPress. Use it to start an Affiliate Program for your products to dramatically increase traffic, attention, and sales. Affiliate Royale works with every edition of MemberPress but is only included with the Pro Edition of MemberPress.