Since a group’s state is a binary sensor type display it would be nice to add some type of group config options like device-class to be able to change the group state display.
Instead of just showing on or off if I have a group of window sensors it could say “Closed” or “Open”
this video might help illustrate it better.
https://www.dropbox.com/s/lph46f56ytlr6p4/hass-group.mov?dl=0
Totally agree. I grouped my motion sensors, so all sensors are clear/detected, but the group is on/off.
Besides that the group state is also manually editable, which it shouldn’t be.
Just assigning a device class to the group would keep things in line.
And if all devices in the group already have the same device class defined, the group should just assume that device class by default.
Is there a solution for this? would love to be able to use this for my doors.
I tried creating a template binary_sensor, which works since you can set the device_class, but when I add it to lovelace I lose the list of doors in the more-info card.
anyone found a solution for this?
We need to find more people to vote for this FR in hope that it will be added to a future release…
Yes! Stumbled upon this today and voted of course. Please implement!
Groups should also be created and edited via the UI - just like a HELPER - with a selector to define the device class 
Right on. Surprised how behind the group integration is. Also, I don’t want a group toggle switch in the UI for a group whose members are uncontrollable, like binary sensor. It doesn’t make sense.
I just voted. I agree with what was said above. The other option would be to create a template binary sensor, for which you can do just about anything, but having the device class attached to a group would be so much easier. At a minimum, if all devices within a group have the same device class, the group should inherit this behaviour.
Please consider this improvement/change…
The devices class above is “Problem” for the individual sensors, yet the group is simply on/off. I understand the group toggle switch could be useful if your group contains only switches or lights, but for sensors, it doesn’t make any sense.
Quite old topic but definitely on that!
I explicitly do NOT like/want to use the group creation via UI, because these “groups” do not give access the the entities they contain 
!
This is why I highly prefer the old-style groups! The only drawback is, that the icons do not change - although the overall state of the old-style groups is detected and reported correctly!
So having a device_class feature for old-style groups would be just a logical step to not only colorize the icon correctly but also choose the corresponding icon!
My topic HERE is also about how to change the group icon and why new-style groups are not the desired solution for that.
