How about a "standard" light switch that is also controllable via Z-wave, which doesn't require Internet access or Wi-Fi or anything like that? Which is what most of the switches in my house are, and really what a proper smart home should be using.
The "Z-wave" function would never be used in my house so it would just be adding cost. Considerable cost at that - a plain white plastic light switch is £1.99, and the "Z-wave" ones I can see on Amazon are all around £20-£40!
Are you sure? The normal switches should be the normal way. But sometimes I've realized I left a basement light on and didn't want to walk downstairs to flip the switch.
There are also odd niches. I have an air compressor in a far corner of my shop (for noise reasons) with pipes running to where I need air. I want to control that without having to walk across the shop. (So far I don't have this because finding a switch that control a multi-horsepower induction motor is hard - most top out an 1/4 horse)
I have no idea if it'll meet your requirements or not, but have you looked at something like this GE direct-wire smart switch? https://www.amazon.com/dp/B00YTCZZF0
I have two use cases for this specific switch that I haven't acted on yet:
* schedule my non-smart EVSE to charge our car when power is cheaper at night
* monitor (but not control) the energy usage of our electric hot water heater. It's the second biggest electricity user in the house but I have to infer how much power it's using based on the other separately metered components.
Cost is the thing holding me back. Will it have positive ROI in a reasonable time for our PHEV minivan that only has a 30KWh battery? Seems somewhat unlikely. Would monitoring the power usage of the hot water heater have positive ROI ever? Also seems unlikely.
I was providing a smart home alternative to your example of having to use an app to turn something on and off. I don't think you're going to find a smart switch, Z-wave or not, for £1.99
Sure. I'm not opposed to people spending large amounts of money on smart devices, I just don't choose to do it myself because in all honesty I don't understand what the point is.
At my first job, I worked for a company that built (among other things) X-10 powerline-control interfaces that would let your PC do the same thing: switch on lights/fans, etc.
As far as I could tell, the only people buying that stuff were hobbyists with a lot of disposable income. Part of my duties was customer support and I can't recall a single instance of anyone doing it for any reason that didn't boil down to "it's cool."
Not making judgements, but I really don't see what the big deal is with getting up to turn on a light, and I live in a pretty big house.
But things that can use it seem to be expensive. I checked, the chips are fairly cheap; but all the PoE stuff I might use aren't "one per light socket" prices. Plus I'd still like a decent mains relay board that is appropriate to put in a wall - the Shellys' are a good form for this, but I cannot see a similar wired solution (although some Sonos devices get close).
Hmm, I'm in the EU and still get hit with customs charges from Chinese items e.g. AliExpress stuff. Not sure if there would be British-made equivalent.
But I'd sooner order from a company that is liable e.g. if the IoT device burns down my house.
