HubSpot CRM - Free CRM software for small businesses.
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.
Less Annoying CRM - A simple customer relationship manager made just for small businesses. Manage contact info, track leads, and never miss a follow-up.
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.
Keap - Grow Sales. Save Time. Get Organized.
Zabbix - Track, record, alert and visualize performance and availability of IT resources