With the 2.24 update Phoscon shows Thermostates so I guess it’s now supported.
Is there a list of supported devices? Are there any recommendation from people already have experience with some?
Is it correct the Ubisys H1 (Heizungssteuerung H1 – ubisys) is not (yet?) suppored? I have really good experiences with Ubisys devices and it supports week plans without gateway which is nice IMO.
I queue myself with this request, I am looking for a good thermostat but, every time I start researching this, I get lost and never get to a conclusion.
I have done a fast check, and nothing (yet) for the ubisys model.
I made good experiences with the Bosch Radiator Thermostat II (see thread here). I have now two of them operating without any issues so far. That is btw. something I cannot claim for my two hands full of Tados which are frequently unreachable. No, I am not affiliated with Bosch 
.