is a cross-platform, open-source ebook reader written in C++ and Qt/wxWidgets-based GUI. Both desktop and mobile handheld versions (Android) are available. It supports a number of non-DRM open ebook formats such as FB2, TXT, RTF, EPUB, PDB, MOBI, DOC and CHM. The interface is designed with simplicity in mind, which allows one to customize several common features such as page layout, font/paragraph style, font size, background/font color etc. Actual formatting of book text is done by built-in DOM/CSS formatter. Cool Reader allows one to add custom CSS files to either override internal CSS files or provide default styles in case internal CSS files do not exist.