API Fortress

API Fortress is a continuous testing and monitoring platform for APIs, that help accelerating releases, at the same time decreasing risk.
Runscope

A set of API debugging and testing tools.
Exoprise

End-to-End network and application visibility/monitoring solution
Checkly

Help Desk Software and Customer Service app. Both SaaS and On-Premise versions.
HaloITSM

ITSM Software | ITIL-aligned Service Desk Software
APImetrics

Real-time API Testing, Ranks, Ratings, Performance tool
AlertSite

Monitor your websites, web apps, and APIs
Odown

Simple uptime tool to monitor your websites and Apis combined with public status pages