How to display device data through Homey on an external web page

I would like to build a small web based dashboard (I have seem Homey Dash but need something to support a specific use case). I have been able to trigger a flow on Homey using WebHooks, but how can I get data from Homey to display on the Dashboard, for example the temperature in a room.

It would be great if someone could point me to information and examples that do this. The Homey documentation sadly lacks this kind of examples.

I assume you mean via the web API?

You want to use the device manager to get the device, then can use getCapability, if you know the exact capability you want - in this case measure_temperature.

I did mean via the web API, thanks that was the missing bit I was looking for

No problem, the full list of capabilities is weirdly hiding in SDK -> Drivers -> Reference.