Practical example - myself and a friend want to edit a route together, in realtime. We are planning a route out together, using Discord for chat, and we're looking at a map and plotting a route together. At the moment, one person (the admin) has to take on the role of creating the route. The only way the other person can see progress is to exit and re-load the admin's shared route. Trying to convey route ideas is all verbal.
What would be so much easier and more powerful is if we could place markers, or a sort of laser-pointer, for each user that the route owner can then "adopt" into the route.... it would allow discussion then; users could place a marker for a desirable place to go or a waypoint they'd like to include in the route. The master owner (the admin) still have to final say on creating the route - he can adopt or ignore those markers into the route - but it allows people to work in realtime discussing and planning the route interactively. Much better than a cycle of emails of "I'd like to go here", followed by a revision to the route by the owner, who then asks the friends to review, who then feedback that he got a waypoint wrong it was supposed to be at the other end of road XYZ, so he reloads the route, fixed it, re-issues it for review, everyone re-loads it, yada yada yada
you get the idea I'm sure!
Think Google Drive collaborative editing of a spreadsheet or document, but on routes instead