Crisp Chat - Multi-channel customer support software

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

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

Chatlio - When you have a business to run, your average instant messaging software just will not do. You need an internal presence upon which your entire team can collaborate on. Read more about Chatlio.

csupport - cSupport offers Live Chat support. Ideal for small businesses and Entrepreneurs Worldwide.

Avochato - Text messaging for your business.