Todo list and Todo annotations can be used for variety of purposes. Todo’s are different from bookmarks in two ways: (1) they can be shared with other users, and (2) they are visible in 3D viewer.
To place a Todo, right click on the location to add the Todo and choose one of the todo types (those ending with 'here').
To change the Todo status to ‘checked’, click to choose the Todo, and right click to choose the menu ‘set checked’.
If you would like to place the ‘Done’ (already checked Todo) without the process of setting it checked, click to choose ‘Done here’ and click.
You can also place Todo in the 3D body view using the right click menu.
You can change the property of a todo in its property dialog, which can be brought up by double-clicking on the todo.