HelpScout - Help Scout is a simple, straightforward way to provide excellent support
UserGuiding - Create in-app experiences with the most straightforward product adoption platform — quick implementation, lasting user engagement.
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.
Usetiful - Fight user churn with great user onboarding. Interactive product tours and smart tips significantly improve your user retention.
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
Userlane - Digital adoption platform with interactive guidance for software applications allowing anyone to understand and master any software from the get-go.