GitHub - SMUsamaShah/fingerink.koplugin: KOreader plugin to draw on old kindles with fingers

GitHub

2 min read Original article ↗

Finger Ink

Draw handwritten notes on KOReader pages with your finger. Designed for touch e-readers without a stylus, including Kindle Paperwhite.

demo.mp4
(FFMPEG commands that compressed this video 35MB -> 3MB) 
ffmpeg -y -i input.mp4 -c:v libx264 -b:v 600k -pass 1 -an -f null NUL
ffmpeg -i input.mp4 -c:v libx264 -b:v 600k -pass 2 -c:a aac -b:a 128k output.mp4

Your ink is saved per page in KOReader's sidecar data, where it can be undone or erased. For PDFs, you can optionally export the ink as native PDF annotations so it is visible in Acrobat, Preview, and other PDF readers.

PDF export is one-way: after export, Finger Ink can no longer undo or erase those strokes.

Requirements

  • KOReader 2026.03 or newer for drawing
  • KOReader 2026.07 or newer for PDF export

Install

Copy fingerink.koplugin into KOReader's plugins directory:

scp -r fingerink.koplugin root@<kindle>:/mnt/us/koreader/plugins/

The final path should be:

koreader/plugins/fingerink.koplugin/main.lua

Restart KOReader after installing.

Use

Open:

Top menu → More tools → Finger Ink

Use Start drawing to enable the toolbar.

  • Draw / Stop — enable or disable drawing
  • Pen / Eraser — change tool
  • Undo — remove the last stroke on the current page
  • Hide — stop drawing and hide the toolbar

One finger draws. Two-finger gestures continue to work normally.

Export ink into a PDF

From the Finger Ink menu, choose:

  • Save this page into PDF
  • Save whole document into PDF

For reliable export, use page view. Continuous PDF view is supported when each stroke stays within one page. Strokes crossing the gap between pages are not exported.

Ink drawn while reflow or page rotation is enabled may not be exportable. Those strokes remain in the sidecar and the plugin explains what to correct.

Limitations

  • No palm rejection.
  • Changing layout after writing can move text while leaving ink behind, especially in reflowable books such as EPUBs.
  • Exported PDF ink cannot be edited by Finger Ink.
  • Fast refresh may look grainy or leave temporary ghosting.

Documentation

  • spec.md — implementation details
  • decisions.md — design decisions
  • requirements.md — original requirements