[bob1029]

I don't think hot water should be this smart.

The last "intelligent" systems that made sense to me in the home are variable speed HVAC and micro grid / solar / battery stuff.

What is the value add to the customer of making hot water an app that can presumably stop working the next time AWS goes down?

[toledocavani]

It can misses some sensor readings, boil the water and scalds the user "automatically". Dumb heaters requires the user to "manually" do this, they never do though. P/S: I'd prefer your stop working scenario