Liquidtext - Click on this link, download the app, then login with the information that was emailed to you.
It is a document reader like a PDF reader, with a bunch of features:
A project in Liquidtext, showing list of documents in the blue lefthand bar, the pages of a document in the middle, and the workspace containing your notes and excerpts on the right.
Squeezing together search results for a word in the document.
An ink link between documents in Liquidtext.