Yeah, at the moment we basically just render the PDF file to an image and show it in a reskinned OCR screen, but with characters invisible + extracted from the file instead of visible + OCRed. The PDF reader library we licensed has a viewer module with nice high-resolution zooming and such but we're waiting for them to add a few necessary features to it before we can start using it - doesn't yet contain the hooks we'd need to support tap lookups.