Our tutor rooms have interactive touch screens. There are a number of tools available that make use of the touch features to allow annotation of screen contents.  Powerpoint (and other microsoft office products) have built in annotation tools accessed from the floating menu on each slide.  The pen tools software allows you to use the screen as a white board, and to import images to the white board for annotation.  There is also an overlay mode which allows annotation of any content on the screen.  These features are nicely demonstrated in this training video from Sharp. https://www.youtube.com/watch?v=mD6qHduvJ70

As with all of these technologies practice makes perfect.  Feel free to schedule an individual tutorial with an ESS member for more help.