The set-up interface is challenging and after our power went out for several hours recently I have been unable after three tries to reconnect my phone to the 4 thermostats in the house. I will have to call for a service person to talk me thru it.
My tstats seemed to have an issue connecting to WPA-2 networks. I ended up having to create an extra unsecured (with MAC filter) network for them to connect to.