calibre Alternatives

Okular

Okular is a universal document viewer based developed by KDE. Okular works on multiple platforms, including but not limited to Linux, Windows, Mac OS X, *BSD, etc. Okular combines the excellent functionalities with the versatility of supporting different kind of documents, like PDF, Postscript, DjVu, CHM, XPS, ePub and others. Okular is a Free Software PDF reader.

Features:

• PDF annotation
• Lightweight
• Low memory usage
• Export to PDF
• Tabbed interface
• Text to Speech
• Chapter cursor
• Document reader
• Fill PDF Forms
• Text Highlighting
• Trim margins

Apple Books

iBooks is an amazing way to download and read books. It includes the iBookstore, where you can download both the latest best-selling books, and your favorite classics. Browse your library on a beautiful bookshelf, tap a book to open it, flip through pages with a swipe or a tap, and bookmark or add notes to your favorite passages. iBooks supports the ePub and PDF file formats.

Features:

• Android Sync
• Built-in Commenting System
• Free books
• Library management
• Text Highlighting

Cool Reader

Cool Reader is fast and small cross-platform XML/CSS based eBook reader for desktops and handheld devices. Understands a number of text document formats, suppurt OPDS (in new ui-opengl version). Fully customizable palette, text reformatting with any font size, font antialiasing, extra smooth scrolling and a lot of other features turn reading into a pleasure. Read Aloud function saves your eyes.

Features:

• Interface Overlay
• Library Manager
• Portable

Data Crow

Data Crow is the ultimate media cataloger and media organiser. Always wanted to manage all your collections in one product? You want a product you can customize to your needs? Your search ends here! Using Data Crow allows you to create a huge database containing all your collected items. You can use the excellent online services to retrieve the information instead of typing all the information yourself.

Features:

• Library
• Categories
• CD Database

Document Viewer

Document Viewer is a highly customizable document viewer for Android, fork of the last GPL version of EBookDroid . Supports the following formats: - PDF - DjVu - EPUB - XPS (OpenXPS) - CBZ (Comic Books, no support for rar compressed CBR) - FictionBook (fb2) Collaboration with electronic publication sites and access to online ebook catalogs is allowed by the supported OPDS protocol.

ReadEra

ReadEra - reading books and viewing documents. The app is completely free and contains no ads. Open and read book files in EPUB, PDF, DOC, DOCX, RTF, TXT, DJVU, FB2, MOBI and CHM formats. Supports chapters, bookmarks, page style. Automatically saves the current reading position. Automatic detection and display of the list of all supported documents on your device.

Features:

• Auto fetch album covers
• Education
• Fullscreen support
• Material design
• Night mode/Dark Theme