One of the popular requests has always been the LCD UI. The LCD UI so far has been very sluggish due to the fact that we use the HABPanel. HABPanel is an addon of openHAB that allows easy UI modifications but on the other hand it is very heavy for our little Pi Zero CPU-wise.

So we removed it and redesigned a new UI for the LCD (the phone app UI stays the same). It is based on pure HTML, CSS and Javascript and talks to openHAB via MQTT over websockets. We had to compile our own mosquitto server as the standard Raspbian package does not support websockets yet.
We built a little proof-of-concept UI with just 2 buttons adjusting the temperature setpoint and from another tablet we observed the speed the change is propagated. The results prove us right on deciding to go that way.

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