Re: 100℃ ??
"For this idea to work properly, you'd need a barometer built in to the kettle, feeding it's output to the off switch."
Or, perhaps, it could use the built-in assisted GPS to determine its current location, look up the local weather report on the Internet, and then use that information to determine when the boiling point of water.
I can't imagine how anyone ever knew that water was boiling before The Internet Of Thingees arrived.