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.
Roby - Refreshingly simple helpdesk for Slack & Teams users
Talkus - Chat with your website users from Slack
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
Sidequest for Slack - Create and track personal or support team tasks, 100% inside Slack.
Crisp Chat - Multi-channel customer support software