Not Andy here, but I don't see how you could use this app for that--its purpose is quite different (to automate the resetting of devices when you need to pair them, especially things like smart bulbs where the sequence and timing of on/off events tends to be different for each brand and hard to remember).
I think you're looking for something like Device Watchdog. There is another similar app, but I can't remember its name. Device Watchdog can monitor your devices for a "last activity" time and notify you when one hasn't generated any activity for the amount of time you specify. (You'll have to know your devices and the type of traffic they produce--for example, Xiaomi devices tend to report in every hour for at least a checkin, my Iris v2 motion sensors tend to report in every few hours for a temperature or battery report even without motion, many of my Z-Wave sensors are configurable but will only check in once or twice a day without other activity to make them do so, and a lot of my non-metering smart plugs don't generate activity at all unless turned on or off.) It can also monitor battery, but I find activity to be far more reliable even if not as proactive (and I think SHM or RM could do something natively if that's all you wanted).
