I have a notification sent to my Alexa devices and phones during arming. I also set the Inovelli notification LED(s) on my Inovelli switches to a specific color. Then I can easily check in most rooms and confirm that the system is armed.
I use leak alerts and they work well...when my water heater died/started leaking when we were away on vacation HSM turned off our main water valve and sent me alert texts as expected so I could contact my neighbor to ask him to confirm that the leak was caught quickly enough that there wasn't any flooding (and there wasn't).
I get a notification from Pushover when it is armed, disarmed, or activated. I also have several DNLA speakers that announce it as well, same thing for leak alerts.