pdf-annotation

PDF++: the most Obsidian-native PDF annotation & viewing tool ever. Comes with optional Vim keybindings.

Open Paper is a workbench for managing your research library. Read, annotate, and understand your papers all in one place. Use an AI assistant to conduct your literature review.

An annotation extension based on the PDF.js viewer. Supporting the editing of existing PDF file annotations, posting comments, replying, submitting annotation data, and loading for further editing. 一个基于 PDF.js 阅读器的批注扩展，支持对现有 PDF 文件批注的编辑、发布评论、回复、提交批注数据以及加载后续编辑功能。

Annotation layer for pdf.js

Backchannel brings the internet's conversations into whatever you're reading. It blends Hacker News, Bluesky, Reddit, and more into a single discussion thread beside any page, then brings those sources together into a blended front page when you're ready to find something new.

The Google Scholar PDF Reader browser extension, now with annotations!

Modular multi-screen pdf presentation viewer

Alfred Workflow to extract annotations from PDF files.

C# and VB.NET samples for Docotic.Pdf library

MAINTENANCE-MODE: Simple "digitial paper" for note taking and PDF annotation. Heavily inspired by Xournal.

📄 Set of modern React components for PDF highlighting

A React component for annotating PDF, powered by PDF.js and RecogitoJS

React PDF viewer & annotator SDK — highlight, markup, ink, shape, stamp and signature annotations with comments, review workflow and collaborative permissions. Export to PDF/Excel. React PDF 查看与批注 SDK， 支持高亮、笔迹、图形、印章、签名、评论审阅与协作权限。

Full-featured PDF viewer with enhancements especially for academic papers

Theses-Checker is a tool for students and teachers alike to check theses for frequent typographical errors and see content analysis for quick evaluation on it's length. (This program is a part of a bachelor's thesis.)

An Obsidian plugin that synchronizes selected Zotero full-text items with your vault in realtime, vectorizes them and lets you chat with your pdf documents.

A cross-platform PDF application built on the UI views and PDFium from chromium

Vue3 PDF viewer & annotator SDK — highlight, markup, ink, shape, stamp and signature annotations with comments, review workflow and collaborative permissions. Export to PDF/Excel. Vue3 PDF 查看与批注 SDK， 支持高亮、笔迹、图形、印章、签名、评论审阅与协作权限。

A completely free PDF coordinate annotation tool that lets you click anywhere on a PDF document to insert precise X,Y coordinates

ElasticPDF is a professional PDF reader and editor for Web, desktop and mobile, with text editing, image editing, annotations, page operations and document export, while keeping files processed locally for better privacy. ElasticPDF 是一款专业的 PDF 阅读与编辑器，支持 Web、桌面端和移动端，提供文字编辑、图片编辑、批注、页面操作和文档导出，并通过本地处理更好地保护文件隐私。