Qpdf Tools is an easy-to-use Qt interface for Ghostscript and Stapler, which makes it possible for normal users to manage their PDFs.
DiffPDF
DiffPDF is used to compare two PDF files.
PDF Mix Tool
PDF Mix Tool is a simple and lightweight application that allows you to perform common editing operations on PDF files.
Krop
krop is a simple graphical tool to crop the pages of PDF files.
PDFslicer
A simple application to extract, merge, rotate and reorder pages of PDF documents
PDF Umhleli
Small python-gtk application, which helps the user to merge or split pdf documents and rotate, crop and rearrange their pages using an interactive and intuitive graphical interface
I-Master PDF Editor
Master PDF Editor is the optimal solution for editing PDF files in Linux.