MarginNote 4

MarginNote 4 is an all‑in‑one application for reading, learning, and managing PDF and EPUB documents. It lets users highlight, annotate, and add pen strokes directly on the source material, while preserving the original file. The app also supports creating and visualizing mind maps, allowing knowledge to be organized hierarchically and explored from multiple angles.

The software is aimed at students, researchers, and anyone who engages in deep, metacognitive study. By stamping each interaction with its context, MarginNote enables users to accumulate and, spark new ideas, and track the evolution of their understanding over time. Note cards generated from highlights can be reorganized and referenced later, supporting iterative learning cycles.

Distinctive features include flexible “Extend Note” spaces that let users write without altering the original document, and the ability to collapse and later restore less important pages. These tools are designed to streamline knowledge synthesis and help users align learning across diverse sources.