What it does
PDF Annotator adds typed and handwritten notes, highlights, drawings, formulas, and images to PDFs. It also organizes documents and measures distances, areas, and angles in plans.
Mark a plan with distance, area or angle measurements, then add written explanations on the same PDF. Teaching notes can include handwritten work or LaTeX formulas. Save the PDF for recipients to view and print in an ordinary reader, or present it full-screen. The Windows app has a 30-day full-feature trial. Its perpetual licence is per user, including network users; later major upgrades are optional purchases unless covered by Upgrade Assurance.
Strengths
- Includes formula annotation and measurement tools alongside handwriting.
Watch out for
- Windows 10/11 software with a time-limited trial; network licensing counts users, not simultaneous sessions.
Best for
- Teachers, engineers, and reviewers marking up PDF pages
Sources
- PDF Annotator - PDF Editor & Annotation Software for Windows (Oct 26, 2026)
- PDF Annotator perpetual per-user licensing FAQ (Oct 26, 2026)