My ideal version of this kind of monitoring is an interface that lets me teach an app what doing things in the house sounds like - new activity name: shut door and lock > record a few runthroughs; then log when it happens, offer push notifications, etc. I have an induction range that helpfully makes lots of beeping noises while many gas ones do not (but also turns itself off), so that would also be possible.
IoT seems to be overengineering for these use cases. Doors that automatically lock when closed, gas that automatically turns off after a certain time (mechanical timer), solves the problem without the need for adding always-on electronics. These features are standard in a large number of apartments in Korea.
GP was talking about monitoring. Answering the question, "did I lock the door", doesn't require an Internet-connected lock with electronics and actuators. A simple backscatter status reporter using the tech presented in this article would be more than enough. Ditto for the gas cooker.
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And speaking of smart locks - in the current IoT - that is, cloud-connected - version, they are just idiotic. Such things shouldn't be vendor-locked and their core functionality should be available over LAN. Even that PCMag article doesn't seem to recognize it, as they don't have an "works without Internet" row in their table.
I'm definitely not an advocate. Anytime someone asks me about smart devices/IoT, my recommendations always defaults to "generic" devices. I think we give up too much of our privacy and control to vendors - especially when there are solutions that don't require cloud servers.
Smart locks and some HASS script can do the lock the door thing.
Although you might just have it monitor your housemates smartphone location and lock your doors if all phones have left the house. If you don't want it to lock, it will just push message you the lock state.