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

Drift - A messaging app that helps you grow your business.

Maian Support - Free responsive PHP Helpdesk System

Clari - Clari is a predictive analytics platform for sales people.

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

Saleswhale - Saleswhale uses AI to engage every lead over email, qualify them, and identify leads that are ready to buy.