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
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
PandaDoc - Boost your revenue with PandaDoc. A document automation tool that delivers higher close rates and shorter sales cycles. We've helped over 30,000+ companies.
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.
Freshservice - Freshservice: the one-stop cloud solution for all your IT management needs.
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.