WordPress - WordPress is web software you can use to create a beautiful website or blog. We like to say that WordPress is both free and priceless at the same time.
Zabbix - Track, record, alert and visualize performance and availability of IT resources
Pendo - Pendo helps product teams understand and guide users to create product experiences that customers love.
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.
Gotcha - User-centric analytics & triggers, driven by micro-surveys
Prometheus - An open-source systems monitoring and alerting toolkit.