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
Assist - Bring the best services to your favorite messaging apps
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.
One Click Feedback - One click feedback for your newsletter
Survicate - Collect feedback on your website and find out more about your visitors.
Ringbot - Have a bot call someone and tell them your message!