I'm unaware of many devices that output audio to multiple distinct bluetooth targets simultaneously. Bose have that feature as part of their app, but I don't think it's a standard thing as a rule.
Here is the abstract, you can see that it clearly is about the interface of creating and controlling the play group:
> A multimedia controller including a processor, the controller configured to: provide a user interface for a player group, wherein the player group includes a plurality of players in a local area network, and wherein each player is configured to playback a multimedia output from a multimedia source; accept an input to facilitate formation of the player group, indicating that at least two of the players in the local area network are to be included in the player group; for each of the plurality of players within the player group, accept an input to adjust a volume associated with the player, that causes the player to adjust its volume; and accept an input to adjust a volume associated with the player group, wherein the input to adjust the volume associated with the group causes the players in the player group to adjust their volumes.
> This application is a Continuation of U.S. Ser. No. 12/035,112, entitled “User Interfaces For Controlling And Manipulating Groupings In A Multi-Zone Media System”
Here’s another example. Wouldn’t it be neat if the tree control in your file browser could have an icon that represents more than 1 file. That idea may or may not have much value. But you better not implement that idea because IBM has a patent on it.
Patents in software rarely meet the bar that most people have of inventions.
the simple elegance of the following has been lost:
"To promote the Progress of Science and useful Arts, by securing for limited Times to Authors and Inventors the exclusive Right to their respective Writings and Discoveries."