Pingdom - With website monitoring from Pingdom you will be the first to know when your website is down. No installation required. 30-day free trial.
WP Engine - Hassle-Free WordPress Hosting
UptimeRobot - Free Website Uptime Monitoring
dotCMS Cloud - dotCMS Cloud is a Hybrid Content Management System that delivers enterprise-class web content management, simple website creation, and collaboration for agencies, teams, and small and medium-sized businesses.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Optimizely Digital Experience Platform - Optimizely Digital Experience Platform is a digital experience platform offering A/B and multivariate testing tools that empower digital marketers without code and enable data-driven decisions.