UptimeRobot - Free Website Uptime Monitoring
Appogee Leave - PARIM Workforce Management Software
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.
actiPLANS - actiPLANS is a simple-to-use online tool that provides a clear view on the corporate work schedule and shows who and when is taking a leave.
StatusCake - Website Uptime Monitoring & Alerts – Free Unlimited Downtime Monitoring
Absence - Employee vacation tracking system