PDF4QT is described as 'Open-source PDF viewer/editor using Qt framework with C++ library, multithreading, hardware rendering, encryption, text layout, and form tools' and is a PDF Reader in the office & productivity category. There are more than 100 alternatives to PDF4QT for a variety of platforms, including Windows, Linux, Mac, Web-based and Android apps. The best PDF4QT alternative is SumatraPDF, which is both free and Open Source. Other great apps like PDF4QT are Okular, Foxit PDF Reader, PDF Arranger and PDF-XChange Editor.
Comprehensive solution for editing, signing, form filling, OCR scanning, commenting, converting, and redacting PDFs, with AI-driven analysis and content extraction, data export to spreadsheets, text-to-speech, seamless use across desktop and mobile, and batch processing.
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...
PDF viewer for macOS supports scientific papers, annotations, highlights, bookmarks, split view, exporting notes, AppleScript, multiple annotation types, bibliography integration, full-screen, search, and compatibility with various macOS versions.
Now also called DiffPDF-FOSS, DiffPDF was free and open-source until version 2.1.3. It was then phased out and superceded by commercial DiffPDF.
Free (and open source) editor for manipulating PDF documents. GUI version + commandline interface. Scripting is used to a great extent in editor and almost anything can be scripted, it is possible to create own scripts or plugins.
A privacy-first, client-side PDF editor that runs in your browser. Edit, annotate, merge/split, compress to target sizes, OCR scanned PDFs, and convert files—no signup, no watermark.
ClarifyDocuments is a free AI tool that converts PDFs, images, and slides into clean, editable text. It automatically cleans, organizes, and processes content in any language, helping students and educators focus on learning.
Atril is a simple multi-page document viewer. It can display and print PostScript (PS), Encapsulated PostScript (EPS), DJVU, DVI, XPS and Portable Document Format (PDF) files. When supported by the document, it also allows searching for text, copying text to the clipboard...
Zathura is a highly customizable and functional document viewer. It provides a minimalistic and space saving interface as well as an easy usage that mainly focuses on keyboard interaction.
qpdfview is a Qt-based tabbed document viewer using the Poppler library for PDF rendering and CUPS for printing. Support for the DjVu and PostScript formats can be added via plugins.
LiquidText offers a fast, natural way to review, gather, and organize information across all your docs: then apply the results to writing reports or simply studying. Pull out key facts and connect them together
Provides editing of text, images, and objects in PDFs, annotation options, OCR for scanned files, conversion to multiple formats, form filling and signing, page management, merging and splitting, cloud integration, camera to PDF functionality, and sharing tools.
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