What are some alternatives?
Marketing Optimizer - Optimize conversion rates, increase lead-to-close ratio, and resell leads easily. Includes complete WordPress integration.
Referral Candy - Run a fully automated, customizable and easy to integrate referral program
SendX - SendX (https://sendx.io) provides remarketing and retargeting tools for web businesses. You can use popups, landing pages, email, web push notification, automation workflows and FB / Google retargeting to drive more revenue.
TapMango - The most comprehensive & feature rich loyalty program on the market. Keep your customers coming back with a rewards program fully branded to your business
SutiCRM - CRM software provides suitable optimization techniques to engage and serve existing and prospective customers.
Referral Rock - Referral Rock provides online referral marketing automation software that helps business get more customers using the network