Originally Posted by sglinert
I can't believe with all the reader people out there, nobody can recommend a speedy PDF reader app that doesn't gum up the works with annotations.
This has come up loads of times - did you search?
Anyway - cloudreader is the fastest I've used. Though I'm not sure how the new version looks as I believe it's moved to an ad funded model. I've avoided updating so far.
An awful lot depends on your PDF file though. Both in terms of general sizing etc but also the structure and how it's been made.