ApowerPDF is a professional PDF editor which helps people modify PDF content with ease. It has a clear and easy-to-go interface, which won't bring too much trouble to users to manage their PDF documents. Also, it can convert, rotate, split, extract, protect and unlock PDF files. Also, users can use it as a printer or PDF reader, as it has bookmark, and annotation features, etc. What's more, the program allows people to create PDF forms, sign PDF and many more, which can solve most PDF problems when people are processing PDF documents.
Icecream Apps PDF Editor - Excellent powerful tool to edit PDF, annotate PDF, redact, protect and more.
Xfce - Xfce is a lightweight desktop environment for UNIX-like operating systems. It aims to be fast and low on system resources, while still being visually appealing and user friendly.
Classic PDF Editor - View, Create, Convert and Edit PDF Files
KDE Plasma Desktop - Plasma Workspaces is the umbrella term for all graphical environments provided by KDE.
PDF Reader Pro - PDF Reader Pro is an all-in-one PDF office supporting to Read, Annotate, Edit, OCR, Convert, Create & Fill Form, Sign PDFs, TTS on Mac, iOS, Android, and Windows.
LXDE - Why will you like it? Less resource needs. You can use it on your less-pricey embedded board or salvaged computer. Component-based design. Don't want something in LXDE, or you don't want to use LXDE but only part of it?