I've taken the XML for the article, and redisplayed it as HTML, with (most) of the citations highlighted in blue. If you touch one (or click on it if you're using a desktop browser) then you'll see a popover with some basic bibliographic details. For some papers which are Open Access I've extracted thumbnails of the figures, such as for "PhyloFinder: an intelligent search engine for phylogenetic tree databases" (doi:10.1186/1471-2148-8-90), shown above (and in more detail below):
The idea is to give the reader a sense of what the paper is about, beyond can be gleaned from just the title and authors. The idea was inspired by the Biotext search engine from Marti Hearst's group, as well as Elsevier's "graphical abstract" noted by Alex Wild (@Myrmecos).
Here's a quick screencast showing it "live":
iPad citation popover from Roderic Page on Vimeo.
The next step is to enable the reader to then go and read this paper within the iPad web-app (doh!), which is fairly trivial to do, but it's Friday and I'm already late...