Heartbeat monitors are a special kind of push monitor. Instead of using a script to send us data, all you need to do is visit a special URL we give you. When you visit the URL it will count as a successful check. If we don't receive a visit in (x) amount of minutes, we will mark that monitor as down and trigger any notifications you have setup.
If you have multiple app servers that live behind a proxy, you won't know if an individual server is having trouble as traffic should be moved to the working server. With a heartbeat monitor, you can have each app server checkin with HitMyServer so you know it's running.
Getting emailed every time your cronjob fires off can be annoying. Instead use a heartbeat monitor and get notified when it doesn't go off. Below is an example for how easy it is to setup.
* * * * * /my/command && curl https://hitmyserver.com/heartbeat/[callback-url]