Screenshot: Khamosh Pathak
If you deal with a lot of PDFs for work, you should consider using a separate app for managing all your PDFs—and GoodReader is as good as it gets.
It offers a full-blown file management system for your PDFs, allowing you to organize them in multiple folders and move them around with ease. You can also connect to cloud storage services like Dropbox, OneDrive, Google Drive, and more. This lets you download, upload, and sync changes to existing PDFs without switching over to a different app.
GoodReader is a paid app ($5.99), but its one-time fee is worth it. You get PDF reading, annotation, and editing functions for this price.