A lightweight in-app canvas for sketching, annotating, and signing. Users draw with smooth ink, switch colors and stroke widths, undo/redo edits, and export the result (including base64) for storage or upload. Optimized for touch, mouse, and stylus with crisp rendering on all screens.

Functionality

• Smooth freehand ink with optional pressure/velocity smoothing

• Pen, highlighter, and eraser tools with adjustable stroke width

• Quick color palette + custom color picker (HEX/RGB)

• Undo/redo history, clear canvas, and partial erase

• Save/export to base64, PNG/JPEG (transparent or solid background)

• Optional background image/grid and watermark overlay

• Shape tools: line, arrow, rectangle, ellipse (toggle fill/outline)

• Text tool with font size, weight, and color

• Image stickers/stamps; drag, resize, rotate

• Pan/zoom and fit-to-screen; high-DPI rendering

• Multi-layer drawing with bring-to-front/send-to-back

• Autosave draft and restore on reopen

• Keyboard shortcuts (web) and haptic feedback (mobile)

• Theming: light/dark UI, radius, shadows, toolbar position

• Callbacks: onStart, onChange, onSave, onClear, onError

• Accessible controls, large hit targets, RTL/localization ready

Use cases

• Signature capture for forms, deliveries, and approvals

• Whiteboard sketches in education, meetings, or support chats

• Annotating screenshots, photos, and PDFs inside the app

• UX/UI feedback markups for design review

• Doodle notes, mind maps, and quick idea boards

• Field service reports with on-site markup + signature

• E-commerce returns/confirmations requiring signatures

• Onboarding tutorials and explainer drawings

• Kids’ drawing/learning apps and creative tools

• Medical/inspection diagrams with layered annotations

Keywords
canvas drawing, signature pad, freehand sketch, digital ink, annotation tool, whiteboard, drawing board, pen tool, highlighter, eraser, undo redo, stroke width, color picker, base64 export, PNG export, JPEG export, transparent background, shape tools, text tool, stickers, zoom and pan, high DPI, autosave, watermark, background image, layered drawing, keyboard shortcuts, haptic feedback, responsive UI, mobile web, Flutter widget, FlutterFlow component, offline friendly, localization, RTL support, accessible controls, premium styling.