Open source
Free screen annotation software for Windows, macOS and Linux. Highlight details with arrows, add Markdown notes and capture screen regions during calls, lessons and presentations. Save your explanations as editable PNG files to share with colleagues.
For teaching, walkthroughs and collaborative reviews.
Explain code, designs and spreadsheets in the app you are presenting.
Add structured notes and attach arrows to them.
Place screen regions on the canvas, then move and resize them.
Save an image and reopen it later to keep editing its objects.
Hold Alt to interact with underlying windows on Windows and macOS. On Linux, use Esc, the mode button or the global hotkey. Installers do not yet carry a developer certificate; your OS may ask you to confirm launch.
Documentation
Latest releaseSource available
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