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.
PuTTY - Popular free terminal application. Mostly used as an SSH client.
NewRelic - New Relic is a Software Analytics company that makes sense of billions of metrics across millions of apps. We help the people who build modern software understand the stories their data is trying to tell them.
MobaXterm - Enhanced terminal for Windows with X11 server, tabbed SSH client, network tools and much more
Zabbix - Track, record, alert and visualize performance and availability of IT resources
iTerm2 - A terminal emulator for macOS that does amazing things.