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

Assist - Bring the best services to your favorite messaging apps

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

One Click Feedback - One click feedback for your newsletter

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

Ringbot - Have a bot call someone and tell them your message!