muPDF

No lag. Nuf said.

http://www.mupdf.com/

Spotlight on Invention: Skim

So the other day I was on the train coming back from Boston (thanks again to my sister for showing me around) read some more of this and I thought "Hey, wouldn't it be great if I could highlight and annotate this like a real book?"

Much to my surprise, someone has beat me to it. I'm still getting used to it but Skim looks amazing so far. Two thumbs up.

The saying "great minds think alike" comes to mind :P