Instabug - The top apps in the world rely on Instabug for beta testing, user engagement and crash reporting.
HiOperator - HiOperator is a virtual assistant that answers phone calls, chats with customers, provides in-app help, takes orders, and provides support.
Disbug - Bug reporting tool that records screen and posts to Jira along with console & network logs
Zendesk - Zendesk is a beautiful, lightweight help-desk solution.
Monitor Buddy - Simple & cheap uptime monitoring service
Intercom - Intercom is a customer relationship management and messaging tool for web businesses. Build relationships with users to create loyal customers.