STDU Viewer is a compact viewer for many computer file formats.

Sumatra PDF is PDF reader and writer for Windows.

Okular is a universal document viewer based developed by KDE.

MuPDF is a free and open-source software framework written in C that implements a PDF, XPS, and EPUB parsing and rendering engine. It is used primarily to ren…

Master PDF Editor is а complete application for editing PDF documents and PDF files for Mac OS X, Windows and Linux.

EBookDroid is a highly customizable document viewer for Android.