In Festival Jam Stage, whenever you jam or enter a jam circle, the UI shows who is playing what in the bottom left corner:
As far as I am aware, this is currently not possible to enable and is not present in any other Islands. Otherwise, a user must bring up their emote/jam wheel to see what is currently playing which is tedious.
If this was a feature that could be enabled for certain Islands, it would make Jam Loop usage more intuitive and encourage people to participate.