It's easy to dismiss this as a crazy idea and an example of a crazy luxury, but just 100 years ago many people were heating water on a fire to fill a tin tub in the living for a bath. Having a bathroom with adjustable temperature from a tap and an indoor toilet was a luxury. Yet nowadays, who would buy a home without a bathroom? What will the bathroom 100 years from now look like? Adjustable temperature for each member of the family, tailored to their preference with time dependent variations? Cool shower in the morning to wake them, warm shower at night to relax? Seems crazy to us now, but I don't think it's unfeasible that such a system might become expected.
But of course there are many wrinkles to iron out on the way, but that is the case with every new technology. Just don't take your non waterproof phone in the shower.
I can think of numerous ways to make an excessively complex electronic shower control that don't involve a smartphone and cannot think of a single benefit of integration with a phone. I'm not some old fart who refuses to use newfangled tech either, I love my smartphone but this is such a completely moronic idea that I don't even know where to start.
It reminds me of those horrid climate controls in cars, I've never used one that worked worth a damn, they all seem to want to turn the fan on full blast and fail miserably by trying to control the ambient temperature in what is effectively an uninsulated greenhouse rather than controlling the temperature of the air coming out the vents. None of them work as well as a simple mixer valve and manual fan control. This shower is a similar gimmick, technology for the sake of technology, not because there's a problem that needs solving.
Can't see how that would work with an Electric Shower, which is very common in the UK/Europe.
Electric showers warm up nearly instantly, though.
It's only needed for boiler-driven showers where there's a delay in getting the heat exchanger up to temperature and also you have to flush all that cold water through the system -- though in my normal two bedroom house it's hardly a hassle, 20 seconds at most before the water is at the set point.