Hello,
I propose a box that allows the user to enter a value for one or more devices (with the idea of MQTT virtual devices).
In edit mode, one can choose for which features to allow the user to enter data.
In normal mode, a field is available for each device and allows entering and then saving a value.
Use cases:
I have to admit I still haven’t grasped how to use a virtual device (or even what it’s for)
If you could shed some light on this old lantern of mine, or even make a mini-tutorial for the community — unless one already exists and I haven’t found it … 
I’ve been waiting for that one for ages! How come it wasn’t requested before? 
However, for
There is the thermostat (which works very well in scenes)
Which shows we should look into describing the features so that everyone can know they exist / how to use them
I confirm what @GBoulvin says, we already do that in Gladys with many devices already, we’re just missing some devices.
I think we just need to create a very specific request for your need, basically to have a type « Water consumption » and « Gas consumption » in m³?
I think quite a few edit boxes are missing.
For example, I set the Currency feature to « This is not a sensor »
And on my dashboard, I can’t edit it
Yes, it’s done on a case-by-case basis 
In the case of cryptocurrencies, nobody ever asked, so we didn’t do it!
OK, I understand. Thank you.
I will close this request and vote for this one then Catalogue des features supportées en MQTT
Why? In the end you don’t need the history of consumption entries?
Yes, but it’s very specific. I can open another request for these 2 boxs (water consumption in m3 and gas consumption in m2)
Perfect
For feature requests, I much prefer ultra-specific requests to very generic ones!
