Sketch
by Kumin Consulting.

01Get it

Install
in one step.

1. In NextOS, open Settings > Apps > Sources and add https://raw.githubusercontent.com/kumin-consulting/nextos-community-tools/main/catalog.json
2. Open the App Store, find Sketch in the community catalogue and press Install.
3. Approve the permissions it asks for: your home folder (it keeps boards in ~/Sketches), settings storage, the clipboard and intents.
4. Open Sketch from the launcher, or send it a kumin://sketch/open?file=<board name> intent from another app.

• —Version 1.0.0, MIT licence
• —Published 2026-09-17, updated 2026-09-17
• —Needs App Store with native apps
• —Runs on Web
• —Asks for fs:read:home, fs:write:home, storage, clipboard, intents

02Screenshots

03About

04Questions

Where are my boards kept?

Each board is one JSON file in your Sketches folder, named after the board: <home>/Sketches/<name>.sketch.json. It is plain, readable JSON with a schema version, the elements and the last view - so you can copy it, diff it, or open it with anything else. Sketch autosaves as you draw and flushes when the window loses focus.

Does an arrow stay attached to a shape?

Yes. Draw an arrow that starts or ends on a shape and it binds to it: move, resize or rotate the shape and the arrow re-aims itself at the shape's edge, keeping the gap you gave it. A label typed onto an arrow rides its midpoint.

What can an assistant do with it?

Five tools: sketch_list_documents, sketch_create_diagram (describe a graph of nodes and edges and Sketch lays it out in layers, draws it and opens it), sketch_add_elements, sketch_export_svg and sketch_describe, which reads a board back in plain words so an assistant can talk about a diagram it cannot see.

Is the SVG export a real SVG?

Yes - a rectangle leaves as <rect>, an ellipse as <ellipse>, a diamond as <polygon>, and text as <text> with one <tspan> per line. It opens in Figma, Illustrator or Inkscape as editable objects, and the words stay selectable and searchable.

How big a board can it handle?

The canvas culls to the visible rectangle and redraws only when something changed, which holds 60 fps while panning a board of a couple of thousand elements on a laptop. Freehand strokes are simplified as you draw, so pen input does not bloat the file.

What happens if a file gets corrupted?

Sketch tells you what is wrong with it and offers to start a fresh copy; it never writes over the file it could not read, and never shows a blank window. Elements it cannot read inside an otherwise valid file are dropped and counted, so one bad shape cannot cost you the board.

Does it need the network?

No. Sketch asks for your home folder, local settings storage, the clipboard and intents - nothing else. It has no network permission at all, and nothing you draw leaves your browser.

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