Documents by Readdle - A central hub for all your files.
ApowerPDF - ApowerPDF is a versatile PDF editor which also features as PDF converter, viewer, creator and more. It provides a perfect solution for all users.
Documents Pro 7 - The ultimate all-in-one mobile office suite for the iPhone and iPad with 8 premium apps in 1.
Icecream Apps PDF Editor - Excellent powerful tool to edit PDF, annotate PDF, redact, protect and more.
FE File Explorer - The one-stop files solution
Atril - Atril is a simple multi-page document viewer. Atril is a fork of Evince.