Document360 - Self-service knowledge base software focused on SaaS Products & Enterprise Software Projects.
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
ProProfs Knowledge Base - ProProfs Knowledge Base is a cutting-edge knowledge management software that assists businesses to reduces support tickets by self-help and create online manuals, guides, wikis, documentation, FAQs and more.
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
Onna - Onna centralizes organizations' most common information platforms like Confluence, Slack, Gmail, Drive, and Dropbox.
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.