The HTTP Device is a very powerful Event Device. With this Device it is possible to prepare REST API Calls, therefore you can trigger API Calls towards a third party system very easily and you can actually generate multiple of these, so you can switch between them within the Inspector of Just Control.
Furthermore this Device can be a connection to an AJA KUMO or Ki Pro, which means that any AJA KUMO routing changes can be performed or you can send any supported AJA Ki Pro command, such as Play, Record or Stop. Especially the Ki Pro integration can be very useful, as you can trigger backup recordings from within Just Control on AJA Ki Pros. That means, as soon as a recording starts within just:in mac, a recording can be started on Ki Pros as well (the same works for Blackmagic Design HyperDeck devices).
Lastly this Device can be used to connect to a SendGrid Account and therefore can be used to send mails on start and/or stop recordings.