Hyperping - Cheap uptime and performance monitoring with detailed reporting and flexible alerting
Monkey Test It - Primate powered algorithms that scan your site for common bugs and SEO mistakes.
UptimeRobot App - Web, SSL, ports & Cron-jobs monitoring
NIXStats - SaaS monitoring tool for window/linux servers and websites. Think up-time robot but with more features.
Cronitor - Monitor cron jobs, micro-services, daemons and almost anything else, no setup required. Easier cron troubleshooting and no more silent failures.
iCliniq on Telegram - telegram bot that will get answers from real doctors