If there is anyone in class recording a lecture using LectureMonkey – other LectureMonkey users can join in and add bookmarks and comments (or you can use your laptop or iPad to enter comments to a lecture you are recording yourself). Just use the press the button on the top left of the main screen.
As in capture mode, just choose the lecture you are attending (the list won’t be long, since only lectures near you are shown). Now you can enter your bookmarks and comments, and see everyone else’s. These comments are collated and added to the lecture so that they are available to everyone.