My Thermotouch 4+

Only works on 2.4 ghtz and sole band routers, even unchecking the 5ghtz wont work. I had to run a script through telnet to temporarily disable it .... after much angst I got it to connect, but wouldn’t have bought it had I known. There are others on the market that work with dual band routers. Limited functionality on the app,so you still need to manually change some settings on the screen, which is also poor design - its impossible to touch the screen without amending a setting. If my supplier would accept it back I would have returned it ..... very disappointed !!

So after some reading through the comments here, the only way I got this to work was to log into my WiFi hub and disable the 5GHz frequency that my phone with the app was connecting to by default.
Once the hub was limited to 2.4GHz the phone / app connected to the thermostat OK.
I was then able to re-enable the 5GHz frequency and the communication between phone / app and thermostat continued OK.

As for the app itself, it’s very dumb compared with Nest / Hive, allowing only 3 on/off pairings per day Monday - Friday, Saturday, Sunday.

After buying and installing under my new floor tiles and of course paying extra for the wireless thermostat imagine the horror of finding out from the app that this will not work on dual frequency equipment I.e Sky Q absolutely nowhere in product descriptions or the user manual does it state this! Kind of a huge factor in its limitations. Am email to trading standards and a claim through small claims court on the way to recoup all my costs for ripping up the bathroom to take the product out and install a new one!