betterboard

An infinite whiteboard desktop app built for pen displays.
Pressure-sensitive ink, endless canvas, zero friction.

---

betterboard is a desktop whiteboard for macOS and Linux (x64 and arm64), designed around drawing tablets like the Huion Kamvas Pro. Strokes are stored as vectors — pressure-weighted centerlines rendered with perfect-freehand — so the canvas is truly infinite, zooming is lossless, and erasing can remove whole strokes or only what sits under the eraser — ink and image pixels alike.

Features

• Four brushes — pen (pressure-tapered ink), pixel (snaps to a shared world grid, so separate strokes and separate sessions line up — real pixel art), marker (flat chisel tip, translucent, builds up where strokes cross) and paint (a dry bristle brush with a solid body and frayed edges). Stroke width follows stylus pressure via Chromium pointer events; mouse strokes fall back to velocity-simulated pressure
• Infinite canvas — pan, zoom, and rotate freely, with an adaptive dot grid that follows the view
• Stylus-native gestures — the pen's eraser end erases, the barrel button pans, touch pans
• Two eraser modes — remove whole strokes, or sweep the eraser circle to remove whatever sits under it: ink is clipped, and pictures get their pixels carved out directly, with no separate image-editing mode. Either way a gesture is one undo step
• Lasso select — loop your pen around anything to select it, then drag the marching-ants outline to move it; ⌫ deletes the selection, Esc drops it
• Layers — add, delete, rename, reorder by dragging, hide, and dim. Opacity composites the finished layer rather than each stroke, so overlaps never show seams — drop a sketch to 30% and ink over it cleanly. Drawing, erasing and selecting stay on the active layer, so what's underneath is safe
• Animation — a timeline of frames, each with the full layer stack. Add, duplicate, delete and drag frames into order, set the frame rate, and play the loop back. Onion skinning ghosts the frames either side, tinted red behind and teal ahead, with adjustable reach and strength
• Images — paste from the clipboard, drop files onto the board, or insert from disk. They land on the active layer and frame, interleaved with your ink in the order you made things, so you can draw over a reference or paste a screenshot on top of notes. Drag to move, drag a corner to scale, ⌫ to delete
• Magic wand — click a picture to select a contiguous color region, Photoshop-style, with an adjustable tolerance; Background mode selects the whole border-connected backdrop with one click anywhere on the picture. Then Erase selected cuts those pixels to transparency (background removal in two clicks) or Keep only discards everything else. Both are single undo steps
• Workspace picker — the first launch asks whether you're here as a student, artist, animator, or photo editor and arranges the starting layout to match, or Anything for the plain default setup with nothing assumed. Every tool stays available whichever you pick, and View → Choose Workspace reopens the choice any time — picking Anything again is also how you put a layout you have wandered away from back to standard
• Ask / Draw through Yagami — box any part of the board to discuss it or ask the model to circle, connect, annotate, and sketch directly into the selected region. Model drawings are ordinary vector strokes with one-step undo. Use the signed-in coding-agent binaries on this computer directly, or connect to a remote personal Yagami server
• Normalize zoom — one press rebases the current view as the new 100%, restoring the full zoom range without moving a pixel; when you hit the zoom-out floor, the button pulses to offer it
• Undo / redo, dark & light board themes, autosave and session restore
• Export — the current frame's visible layers as a PNG, or the whole timeline as an MP4, WebM or animated GIF. Every frame renders into one canvas sized to fit the whole animation, so nothing shifts between frames; pick the frame rate and the size, and watch it encode
• Save / open boards as JSON

Install

make

One command on either platform; make update rebuilds and reinstalls in one step.

• macOS — installs BetterBoard.app into /Applications and launches it.
• Linux (incl. arm64 Ubuntu) — installs to ~/.local/opt/betterboard with a betterboard command on your PATH, a desktop entry, and an icon. On Ubuntu 24.04+ the install asks for sudo once to setuid Electron's chrome-sandbox (the kernel restricts unprivileged user namespaces there).

Keyboard shortcuts below are written with macOS keys; on Linux read ⌘ as Ctrl.

Develop

bun install     # dependencies
bun run dev     # build renderer + launch Electron
bun run build   # typecheck + bundle (production build)

The renderer is plain TypeScript on a 2D canvas (no framework), bundled with bun build. The Electron main process lives in src/main, the renderer in src/renderer. Animation export encodes in the renderer — video through the browser's own WebCodecs encoders, muxed by mediabunny, and GIF through gifenc — and hands the finished bytes to the main process, which only picks the file and writes it.

Controls

Action	Input
Draw	Pen or left mouse drag
Erase	E, the stylus eraser end, or eraser tool; choose Stroke or Area beside the active eraser
Select an area	S, then loop the pen around it (tap a stroke to select just that one)
Move a selection	Drag from inside the outline
Delete / drop a selection	⌫ / Esc
Magic wand	W, then click a picture; Point selects the color region under the click, Background the whole backdrop, and the slider sets tolerance
Apply a wand selection	Erase selected (or ⌫) cuts it to transparency · Keep only cuts everything else
Erase pixels from a picture	The Area eraser, swept straight across it
Pan	Space + drag, H, middle/right drag, pen barrel button, touch, or two-finger scroll
Zoom	Pinch, ⌘ + scroll, ⌘+ / ⌘− / ⌘0, or the zoom pill
Zoom to fit	⌘1
Normalize zoom	⇧⌘N or the ⤢ button in the zoom pill
Rotate	hold R and drag the dial — snaps near 45° steps; double-click the dial to reset, ⌘1 also squares the view
Brushes	1 pen · 2 pixel · 3 marker · 4 paint
Tools	B/P draw · E toggles eraser/pen · S toggles lasso/pen · W toggles wand/pen · H hand
Ask or draw with AI in a region	A, then drag a box (or ⌥⌘A)
Send · newline · new thread	Enter · ⇧Enter · + in the panel
Paste / insert an image	⌘V (Edit ▸ Paste), drop a file on the board, or ⇧⌘I
Move / scale / delete an image	Drag it · drag a corner grip · ⌫
Timeline	T or ⌘T
Play / pause	Enter (or ⌘↩)
Previous / next frame	← / →
New / duplicate / delete frame	⌥⌘F / ⌘D, or + ⧉ 🗑 in the timeline
Reorder frames	Drag a frame cell
Frame rate · onion skin	The fps field · the ◐ button (⌥⌘O), then its sliders
Layers panel	L or ⌘L
New / delete layer	⌥⌘N / ⌥⌘⌫, or + and 🗑 in the panel
Hide / show a layer	The eye on its row, or ⌥⌘H for the active one
Layer opacity · rename · reorder	The panel slider · double-click its name · drag its row
Stroke size	[ and ] or the slider
Undo / redo	⌘Z / ⇧⌘Z
New / open / save	⌘N / ⌘O / ⌘S
Export PNG · export animation	⌘E · ⇧⌘E, or ⤓ in the timeline
Dot grid · board theme	⌘G · ⇧⌘L
Choose workspace	View → Choose Workspace…
Clear frame	⌘⌫

Asking and drawing with AI

The Ask tool boxes a region, re-renders just that area as a PNG, and sends it with your question through Yagami. Replies appear in the side panel. Ask the model to draw, circle, underline, connect, or annotate and it can add bounded vector commands to the current layer and frame. Those strokes remain editable board content and undo together in one step.

Open File → Yagami Connections… and choose one of two modes:

• This computer — installed CLIs embeds Yagami in BetterBoard. It automatically discovers the Claude Code, Codex, OpenCode, Gemini, or other supported coding-agent binaries already installed and signed in on this machine. No URL or personal API key is involved.
• Remote Yagami server accepts the URL of an existing Yagami server. A personal ygm_… key is available but optional, for servers that require one.

The optional harness/model field follows Yagami routing in either mode: claude, codex, codex:gpt-5.6-sol, opencode:provider/model, and so on. Leave it blank to use Yagami's detected/default provider.

It is entirely opt-in. Worth knowing before you turn it on:

• Optional personal Yagami keys are written to settings.json in the app's user-data directory with 0600 permissions. They never enter the renderer — requests are made from the main process — and only the last four characters are returned for display.
• Nothing is sent to a coding-agent harness or remote Yagami server unless you press Ask. It receives the cropped image and thread messages needed for the request. No other frames, layers, or board contents are sent.
• Conversations are held in memory for the session only. They are not written into board files, so a .betterboard.json you share carries no chat history.
• Any model drawing is validated and limited to simple geometry inside the boxed region; model output cannot execute code or address arbitrary board objects.

File format

Boards are JSON (version 5): lists of frames and of layers (name, opacity, visible, bottom-first), the frame rate and onion-skin settings, a list of strokes — each carrying its color, size, brush, a seed (so brushes with any randomness redraw identically), its owning layer and frame, and [x, y, pressure] points in world coordinates — and a list of images, embedded as data URLs so a board stays one portable file. Strokes and images share a running seq, which is what puts them back in the order you made them. Imports over 1600px on the long side are scaled down on the way in, since a few full-resolution screenshots would otherwise dwarf the drawing they annotate. Plus the camera. Frames and layers form a grid and every stroke sits in one cell of it. Older files still open, each filling in what it predates: version 4 has no images, version 3 no brushes (its strokes load as pen), version 2 no animation (it lands on a single frame), version 1 no layers either. Autosaves go to the app's user-data directory; ⌘S exports a portable .betterboard.json.

Roadmap

• Custom app icon
• Scale and rotate a selection, copy/paste between boards and frames
• Shapes and text
• Pen tilt support