Yes, it's primary purpose is to be a PDF reader/annotator. Though some here refer to it as the "Swiss Army Knife" of apps because of its versatility. Last I checked, it was $4.99 (USD) in the App Store.
I'm not going to say that it will solve your download problem; I can't know that. I will tell you that I think it's one of the best apps out there for reading PDFs (and for file management, file transfer, storage, etc.). As usual, and as always - YMMV.
Marilyn