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.
Jetpack - Jetpack offers SEO and security plugins for Wordpress.
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.
WP User Manager - The most customizable profiles, community builder and membership WordPress plugin
Zabbix - Track, record, alert and visualize performance and availability of IT resources
Project Panorama - Project Panorama is an elegant and reliable WordPress manager plugin that comes with exciting features and tools that will allow managing your multiple WordPress sites with ease.