6Q - 6Q connects leaders to employees through six question surveys and receive actionable 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.
Impraise - Impraise is a web and mobile app for 360 degree feedback and peer coaching
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
SelfStir - SelfStir offers 360-degree feedback system.
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.