Xournal++
FreeHandwrite on a PDF the way you would on paper
A handwriting and PDF annotation application. Use a graphics tablet, touchscreen or stylus to draw, annotate and highlight directly on a PDF, or treat it as an infinitely extending handwritten notebook. It supports pressure sensitivity, multiple pen types, shape recognition, image and audio insertion, and exports annotated PDFs.
Why we picked it
Writing a thought in the margin of a paper, circling errors on a student's work, signing a contract, taking notes on a lecture PDF — all natural on paper, and strangely awkward on a computer. The paid options, mostly tablet note apps, tend to lock you into an ecosystem and bill annually.
Xournal++ is the open-source answer. 15,220 stars, GPL-2.0, currently v1.3.7.
Two main ways to use it:
- Annotate a PDF. Open a PDF as the background and write, draw, highlight and add sticky notes on top. Export as an annotated PDF and anyone can see your handwriting in any reader, with the original file left intact.
- As a handwritten notebook. Start blank, choose a paper style — ruled, graph, dotted, music staves — and write as you would in a notebook, adding pages indefinitely.
Considerable effort has gone into the writing feel: pressure sensitivity for varying stroke width, three eraser modes (stroke section, whole stroke, area), shape recognition that straightens a roughly drawn line or rounds a wobbly circle, and lasso selection to move or scale a region of handwriting as a unit.
Additional practical uses:
- Digital signatures: sign a PDF contract by hand and export it, with no print-and-scan round trip.
- Audio insertion: record while writing during a lecture or meeting, then tap a note later to jump to that moment in the recording.
- LaTeX formulas: typeset mathematical expressions inline, which is genuinely useful for technical note-taking.
Things to know:
- Hardware determines the experience. With a graphics tablet or a pressure-sensitive touchscreen it is excellent; writing with a mouse is miserable — a mouse is fine for boxes and arrows, not for handwriting.
- No handwriting recognition. What you write stays graphics and never becomes searchable text.
- The interface is traditional GTK styling — complete, but not modern or polished.
If you only need typed annotations and highlights on a PDF without handwriting, Okular is lighter. When actual ink is required, Xournal++ is the best free desktop option.