Freeze the size of shapes
A great feature would be to be able to freeze or lock the size of a shape while still enabling that shape to be moved around the mural. Example: I had some peers test out a "claim your space" activity where they would add their name to a circle and then drag the circle to the appropriate space on the page. The first thing that the testers did was the enlarge and change the shape of the circles so that they covered up nearly the entire screen. This is something that would bring in some laughter, but be disruptive to the activity. Being able to have shapes that are a set size but are moveable would be a great feature for this type of activity. Pictured below is how the circles started out in the Claim Your Name space and what participants could end up doing with their circles.
