I was working on a project that includes a drag n drop feature where the user can drag items from a sidebar onto a canvas and move them around. I extracted the drag n drop part of it and made it into a simple example. It uses Models and Collections and sync persistence which essentially makes it into a collaborative connected app. Try running it and then opening a second viewer, e.g. in a browser, when you drag new shapes into the canvas and move them around the second viewer is updated in real time.
Here is the example:
Drag n drop example.zip (7.1 KB)