I see a few reasons these could be useful.

1. A way of communicating while in the "Speechless stage" of huskification.

2. A way of writing down details of what happened for the rescue shuttle crew.

3. Just a diary of how you died.

So basically these should work kind of like the notes from BTE except you can write and create your own drawings with them, which adds on to Captain Tom's hobbies that include, drawing, waxing mustaches, and leather clothing. But the way you might do it is by dragging your mouse while holding down the left mouse button, kind of like this.