In AutoCAD-based 2014 products the Autodesk 360 ribbon tab was introduced that has an option available to collaborate on a drawing with other users using Autodesk 360.
The Design Feed palette provides a way to post and reply to messages, which can include attached images, to colleagues and clients through Autodesk 360. The messages can be linked to locations and areas within the drawing, and can be accessed online by the people that you authorize.
If you notice that the Design Feed palette does not update immediately after you save a drawing in Autodesk® 360, then you can force it to update with a right-click on the Autodesk 360 icon, located on the Windows taskbar, and then select Sync Now.
For more information about the Design Feed Palette, see online Help topic for Design Feed Palette.