First thing I do when I get a smart appliance is scan it with nmap. This has revealed some interesting Easter eggs, like my Davis instruments air quality sensors having a local REST API.
Doing the usual scan against my GE washer and dryer shows that port 53 is listening. What could that be for? Is there a way I can at least query their status locally or something?
When I got the washer and dryer I was excited about the smart home features because getting an alert when my laundry is done or starting the washer remotely so the clothes are done when I get home are genuinely useful features. However, last time I checked the app none of that was available, so I just have these Trojan horses in my home spying on me with no benefit in exchange. Their app wanted my freaking mailing address when I signed up for their mandatory account, so the features mentioned above are the least they could offer in exchange for my digital soul. But I digress.
My fridge is in a similar situation. It commits the additional cardinal sin of ONLY being controllable via the app, with no on-board temp or filter status indicators whatsoever.
The only issue I see is that getting most sensors to work in the fridge/freezer is difficult for 2 reasons, the cold fucks with the batteries and the metal body of the fridge fucks with the signal.
I just used zigbee and put a repeater right next to the fridge. The big ass coin cells in the sonoff temp sensors are lasting around 6 months. Would probably be longer but I have the sensor with a screen in there.
Obviously YMMV if you have a SubZero or something, but in my jankey LG it works fine.
@KyuubiNoKitsune
I use cheap Aqara sensors, in fridge battery hold several months, but in freezer I have to replace them every two months. Attenuation seems to be less of a problem, at least since I switched to Homeassistant with central coordinator and my Ikea ceiling lights in virtually every room act as repeaters. I the beginning I had separate hubs for each ecosystem and consequently 4 poor Zigbee networks.