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.
Usetiful - Fight user churn with great user onboarding. Interactive product tours and smart tips significantly improve your user retention.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Vision Helpdesk - Help Desk Software, Multi-Company Help Desk, ITSM Service Desk & Live Chat Software
Better Uptime - We call you when your website goes down
Site24x7 - Site24x7 offers both free & paid website monitoring services. Monitor websites remotely and receive instant email/sms alerts if your website becomes unavailable. View uptime & performance graphs of your website monitors.