What app do I need to browse and read pdfs in iCloud Drive "Preview" folder?

Can anybody please suggest a simple pdf browser for iOS8 that integrates nicely with iCloud Drive? I just want to be able to browse and read on my iPad pdfs that I keep in iCloud Drive/Preview folder on my Mac.

I have tried various third-party pdf readers, but if they have iCloud Drive functionality they generally insist on creating their own dedicated folder for pdfs on iCloud Drive and cannot read the pdfs that I have in the Preview folder.

In short, I just want a pdf reader for iOS8 that looks and behaves like the rest of the iWorks suite.