SatisMeter - Identify unhappy customers in your web and mobile apps, or via email, solve their issues, reduce churn and grow your business.
UseResponse - Open-source, self-hosted customer feedback software, live chat and helpdesk system that you can install on your server. Organize documentation using knowledge base and get feedback from social networks with centralized system
ShadowAide - ShadowAide provides you with a key way to keep your finger on the pulse of your customers, using our integrated tools for capturing Net Promoter Score and customer feedback.
UserVoice - UserVoice integrates easy-to-use feedback, helpdesk, and knowledge base management tools in one platform that empowers users to speak and companies to understand.
Promoter.io - Promoter is designed to capture actionable and accurate customer feedback that reduces churn and drives growth
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.