You're reviewing a draft on iPad and want to circle a paragraph, scribble 'cut this' next to it, and draw an arrow to a better place. Tapping through menus to pick a shape and a text tool kills the flow.
Freehand ink lets you mark up naturally — same way you'd mark up paper. Flint supports it.
Pen-style drawing
Open annotate PDF, select the pen/ink tool. Drag with your finger (on touch devices), with Apple Pencil (best experience on iPad), or with a mouse (on laptops). Your strokes appear as ink on the page. Lift, draw again, lift. Build up annotations stroke by stroke.
Colour and thickness
Set the pen colour before drawing — typical workflow uses red for issues, black for general notes, blue or green for positive marks. Thickness affects readability: thin for handwriting, thick for circling or emphasis. Switch as you go.
iPad and Apple Pencil specifically
Best ink experience: iPad with Apple Pencil. Pressure sensitivity, low latency, palm rejection — all the things that make ink feel natural. Open Flint in Safari, ink with the Pencil. Saving works the same as desktop: file downloads to your iPad, share via the iOS share sheet.
Limitations of ink vs typed comments
Ink is fast but not searchable. If you scribble 'rewrite this' in ink, no future search finds it. For text that needs to be found again (or quoted in an email back), use sticky notes or text annotations instead. Ink for sketches and emphasis; text for ideas that need to be preserved.
FAQ
Can I erase ink?
Yes — switch to the eraser tool, drag over strokes to remove. Or undo within the session.
Does ink work without a stylus?
Yes on touchscreens (finger) and laptops (mouse/trackpad). Stylus gives the best precision.
Will recipients see ink?
Yes. Ink saves as a PDF annotation and shows in any reader.
What about Apple Pencil double-tap?
Some readers map double-tap to eraser. Flint's web context depends on browser support.
Pick up the pen, mark naturally. Draw on PDF.