Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.

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

tawk.to - tawk.to is a free live chat app that lets you monitor and chat with visitors on your website or from a free customizable page

Trakdesk - Trakdesk is a fully customizable customer support platform with all the bells and whistles you would need to provide exceptional customer support

Zendesk - Zendesk is a beautiful, lightweight help-desk solution.

HelpScout - Help Scout is a simple, straightforward way to provide excellent support