When a team of two or more developers is working on the same project, it would be great if there were annotation and markup tools we could use much in the way Pages, Numbers, and Google docs operate.
It would be great if there were a layer in layout mode that we could show/hide for each member of the development team that would allow us to attach notes to an object or group of objects, and general notes in the margin. Each developer might have their own color, for example, with the ability to comment on other developers' comments.
Maybe a way to set certain areas with a flag that says, "work in progress:Please don't modify"
As long as I'm wishing, some graphic mark-up tools like there are in Apple's Preview and Mail apps so I can draw circles and arrows, etc.
Perhaps a similar functionality could be applied to other areas; something like this would be useful in the script workspace too.