Best PDF Annotation tools

Share a collaborative whiteboard URL and work across unlimited pages with live audio, video, and document annotation.

A multimodal note workspace for handwriting, audio, documents, PDFs, and study materials.

Write naturally by hand and add PDF pages to notes for markup.

An open-source iPad notebook for Apple Pencil writing and PDF markup.

A browser-based shared math canvas for handwriting, graphs, sliders, and PDF assignments.

An open-source desktop notebook for stylus handwriting, PDF markup, layers, and audio notes.

Handwritten study notes, PDF markup, audio capture, and AI-assisted review for students.

A shareable infinite drawing board for handwriting, tutoring, diagrams, and PDF markup.

Draw together on a free whiteboard for lessons, files, and shared notes.

A tutoring classroom with an interactive whiteboard for annotating PDFs, worksheets, slides, and images together.

A teaching whiteboard with video calls, lesson materials, and PDF or image annotation.

A privacy-first, open-source knowledge base for structured personal notes.

A zoomable handwriting and planning notebook with sub-pages and document annotation.

Write and annotate handwritten notes on Android with page layouts, linked notes, and PDF tools.

Write with Apple Pencil in an Obsidian vault and keep handwritten pages beside Markdown notes.

Write or sketch by hand, then convert, search, and organize the result.

A multi-format notebook for handwriting, PDFs, voice notes, and study documents.

Write with a stylus in flexible notebooks that can also hold and annotate PDFs.

A handwritten notebook for Apple Pencil notes, PDF markup, study tools, and creative pages.

Read study PDFs and make notes as part of one annotation workflow.

A handwriting notebook with note-linked audio, handwriting recognition, and PDF annotation.

An Android-first notebook for handwriting, PDF markup, voice notes, and optional web sync.

Share a live board with sticky notes, drawing tools, images, and imported or exported PDFs.

A browser-installed notebook for handwriting, PDF markup, and recorded lectures that works offline.