Cronhub - Cronhub helps you to easily monitor all your cron jobs in a beautiful dashboard. It alerts you when your cron job doesn't run on time or it fails.
Cronitor - Monitor cron jobs, micro-services, daemons and almost anything else, no setup required. Easier cron troubleshooting and no more silent failures.
World Time Buddy - Effortless time conversion and world time.
UptimeRobot - Free Website Uptime Monitoring
Easy Timezones - Easy Timezones is the simplest, easiest way to compare time zones throughout the world. Schedule meetings to suit all your friends, family and colleagues.
Cronly - Keep track of your cron jobs and SSL certificates. Don't let them fail unnoticed.