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.
DbNinja - Web-based application for secure and efficient management of MySQL database servers
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.
Adminer - Adminer (formerly phpMinAdmin) is a full-featured database management tool written in PHP.
Zabbix - Track, record, alert and visualize performance and availability of IT resources
myLittleAdmin - myLittleAdmin is the first web-based management tool specially designed for MS SQL Server.