I have personally used Post Affiliate Pro for almost 2. While I had some small issues, the customer support team quickly resolved them. The software is pretty affordable and has a lot of excellent features and many, many integrations. We took the advantage of free set-up and integration, which was a very nice gesture from the company.
OneLogin - On-demand SSO, directory integration, user provisioning and more
17hats - The all-in-one business system for entrepreneurs.
Okta - Enterprise-grade identity management for all your apps, users & devices
Optmyzr - Optmyzr AdWords Tools. Optimization Solutions, Quality Score Tracker, Landing Page Checker, and more. Free Trial Available.
PortalGuard - A dedicated web-based identity management portal that combines strong authentication with flexible, high-performance integration.
LiveIntent - LiveIntent is a web platform that offers effective e-mail advertising services for marketers and publishers.