@Solla-topee well, you cannot really just use the valves.  You need to pair them with some control of the boiler, so that when even a single valve requires heat, the boiler is activated. When no valve requires any heat, the boiler is off.

The KH100 hub you are mentioning does not provide this function, and its use is honestly very limited, basically when I am far from home and I want to have some form of control on the heating system (with the caveat that I have zero control on the boiler).

Here's for example what competitors do:
http://bit.ly/457251v

Hopefully the scenario is clear, including why a smart thermostat (which controls the boiler) is needed. 

  @BB69 Hi, why not use other brands' smart thermostat (which controls the boiler) and control it with its own app?

  @Summer_S As I described before, the thermostatic valves on the radiators need to inform the action of the thermostat, so that it can power on or off the boiler.  If you have any suggestion that interfaces with the KE100 valves, please let us know!

  @BB69 The Tado setup looks very comprehensive, but also seems pretty expensive.

I went with the Kasa system because my new heat pump CH had unbelievably crude controls (a single manual-set thermostat in the hall!), and I wanted to try individual room control without breaking the bank.

Ideally, I would love individual room (wall) thermostats to control multiple radiators in different rooms at different temperatures, and to adjust the rad valves accordingly and signal to the heat pump to switch on when heat is required.

Instead, my chosen option with the Kasa hub and valaves has been to leave the heat pump on permanently on colder days, and allow the Kasa valves to regulate each room separately.  Not the most efficient method, but it works.  Would an upgrade to a more sophisticated system save money in the long run?  I guess it probably would.

@Bill_C Yes, the ability to switch on/off the bolier (or the pump) based on the actual need would save a lot of money. I know the Tado setup is very expensive, I was just pointing it out in order to offer a clear explanation on how it works, as it seemed I was not clear enough before. What annoys me is the KE100 valves are potentially able to inform a simple switch to set on or off the boiler, and they are cheap, but there's no hardware to do that. 
I will keep looking around and if I find something I will point it here.

@Solla-topee any further comments from you guys?

  @Solla-topee my use case is that I would like to have the boiler turn on when the TRVs are calling for heat. I'd also like to turn the boiler on from the Kasa app. The scheduling on the TRVs is really good and I do like them, but they are limited by the lack of integration with the boiler.

Also the geofencing feature is completely pointless without a smart house thermostat - sure the radiators will be calling for heat but unless the boiler is on 24x7, they won't be hearing up.

Really looking forward to this feature - I'll probably be buying two as I have two heating zones in the house .

If it's not going to be done, can you ar least open up the API so we can integrate more easily with third party options? Currently it's all encrypted so it's not possible to communicate with the TRVs without going through the app.

  @Nav89 

Do we have any update on that? I bought the TRVs a few months ago, knowing the in USA they launch the Smart Boiler Control. I'm super happy with the TRVs, they improve the quality of the room that now are not over heating, but without controlling the boiler, even if all the Radiator are close, I'm still wasting hot water in the pipe through all the house. 

I'm now taking in consideration the T6 wired Thermostat from Honeywell, but this means another app, and is preatty annoying, if I knew back than that after all this month we will be without the smart boiler thermostat in UK i would choose Tado.