Zendesk - Zendesk is a beautiful, lightweight help-desk solution.
Datadog - See metrics from all of your apps, tools & services in one place with Datadog's cloud monitoring as a service solution. Try it for free.
Freshdesk - Freshdesk is a cloud-based customer support software that lets you support customers through traditional channels like phone and email, social channels like Facebook and Twitter, and your own branded community
AppDynamics - Get real-time insight from your apps using Application Performance Management—how they’re being used, how they’re performing, where they need help.
HelpScout - Help Scout is a simple, straightforward way to provide excellent support
Zabbix - Track, record, alert and visualize performance and availability of IT resources