Native macOS app for viewing, annotating, and editing images and PDFs, featuring tools for cropping, rotating, resizing images, rearranging pages, full-screen viewing, markup, document merging, batch conversion, and export in multiple formats.




Skim is described as 'PDF viewer and annotation tool for macOS supports scientific paper reading, note-taking, highlighting, bookmarks, multiple annotation types, and AppleScript' and is a popular PDF Reader in the office & productivity category. There are more than 50 alternatives to Skim for a variety of platforms, including Windows, Mac, Linux, Android and iPhone apps. The best Skim alternative is SumatraPDF, which is both free and Open Source. Other great apps like Skim are Okular, Foxit PDF Reader, Xournal++ and PDF-XChange Editor.
Native macOS app for viewing, annotating, and editing images and PDFs, featuring tools for cropping, rotating, resizing images, rearranging pages, full-screen viewing, markup, document merging, batch conversion, and export in multiple formats.




Create, Convert, Review and Edit PDF Documents on Windows, macOS, and Linux.




Qoppa PDF Studio is the most popular commercial alternative to Skim.
Nitro offers comprehensive PDF solutions for editing, creating, and converting, alongside OCR and e-signature tools. Supports Mac, Windows, and iOS, providing a user-friendly interface with industry-standard security features. Ideal as an Adobe Acrobat alternative.




Xodo is the ultimate cross-platform PDF viewer and annotator. Powerful, fast, and optimized for all phones and tablets, Xodo makes it easy to access, edit, share, sync, manage, sign, and more.




Xournal is an application for notetaking, sketching, keeping a journal using a stylus. It is free software (GNU GPL) and runs on Linux (recent distributions), Windows and other GTK+/Gnome platforms.

The top AEC PDF app to markup and manage drawings and documents. Ideal for replacing pen and paper, avoid printing documents again by using our intuitive feature set that makes marking up a PDF easy. Open or create a new PDF, markup using our extensive array of tools, then save...




A document viewer for the GNOME desktop. You can view, search or annotate documents in many different formats.


Integrating powerful tools for book annoation, mindmapping, flashcards and more, to build up your reading notes as never before.




Document Viewer is a highly customizable document viewer for Android, fork of the last GPL version of EBookDroid .


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.




Simple Android PDF viewer based on pdf.js and content providers. The app doesn't require any permissions.



Open-source PDF viewer and editor using Qt framework, featuring hardware-accelerated rendering, encryption, multithreading, text-to-speech, annotation tools, form filling, high-res monitor support, document compression, audio book conversion, and signature validation.

