Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.
indemandly - Live chat 2.0: Customer messaging that converts
Outbound Apps by Intercom - Embed apps right inside your messages
Message Me - Website to create your contact business card
Live Chat by Sumo.com - Instantly communicate with customers, prospects & visitors
Actions from Slack - Turn Slack messages into tickets, issues, tasks, and more.