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.
WOVER - An intelligent personal emergency platform
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Facebook Safety Check - Connect with friends and loved ones during a disaster
Better Uptime - We call you when your website goes down
Augurisk Now - Localized crime and natural disaster risk alerts