Trello for Slack - Organize anything with anyone, inside Slack
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
Live Chat by Sumo.com - Instantly communicate with customers, prospects & visitors
Halp - Slack-first ticketing for internal helpdesk
Drift - A messaging app that helps you grow your business.
Actions from Slack - Turn Slack messages into tickets, issues, tasks, and more.