EasyCron - Get frustrated with Cron on your server? Hosting limits your Cron use?
Proxyman.io - Proxyman is a high-performance macOS app, which enables developers to view HTTP/HTTPS requests from apps and domains.
crontab guru - The quick and simple editor for cron schedule expressions by Cronitor
httpbin(1) - HTTP request and response service
Cronitor - Monitor cron jobs, micro-services, daemons and almost anything else, no setup required. Easier cron troubleshooting and no more silent failures.
Endpoints - View and respond to requests on an HTTP endpoint