Simon

Simon

Flexible server monitoring

Free 30-day trial. No credit card required. Cancel anytime.
The essential site monitoring tool for macOS. Simon checks servers for changes or failures, and notifies you via email, sound, speech, Twitter, or other means.

You can use it to track updated sites, and to alert you when an important server goes down or recovers. It can be used to monitor your own website and servers, track posts and new comments on your or friends' blogs, check for web mail, get notifications of updates to favorite news and entertainment websites, keep an eye on auctions, communicate with arbitrary servers, and many other uses.
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SOUNDS GOOD? WELL, IT LOOKS GOOD, TOO.
Simon is a gem, and Setapp has many more.
Free 30-day trial. No credit card required. Cancel anytime.