# Stylus — Digital Canvas & PDF

> Pressure-sensitive digital whiteboard and split-screen PDF annotator. Sketch diagrams, derive math equations, and annotate lectures.

## Overview
Stylus is a calm, distraction-free digital canvas and PDF reader engineered for students, educators, and researchers. Whether you are solving calculus problems, annotating a research paper, or sketching system diagrams with a stylus, Stylus delivers sub-millisecond stroke latency and zero-cloud local storage.

## Everyday Use Cases
- Take handwritten lecture notes and whiteboard brainstorming sessions
- Open and mark up heavy PDF textbooks and scientific papers with highlighters
- Typeset complex mathematical equations using inline KaTeX notation
- Draw hand-drawn architectural diagrams and rough geometry with auto-smoothing
- Export vector notes directly into publication-ready PDFs

## Core Highlights
### Pressure-Sensitive Ink
Utilizes perfect-freehand velocity and pressure modeling for lifelike fountain pen and marker strokes.

### Split-Screen PDF Reader
Load multi-page research documents side-by-side with your canvas and annotate directly across margins.

### Mathematical Typography
Render LaTeX and KaTeX formulas directly onto your canvas without leaving the stylus workspace.

### 100% Client-Side Privacy
All sketches, notes, and PDF annotations stay safely inside your browser OPFS and IndexedDB storage.

## Access & Endpoints
- Web Application: https://xicae.dev/stylus
- Live Application: https://stylus.xicae.dev
- REST API: https://xicae.dev/stylus/api
- Model Context Protocol (MCP): https://xicae.dev/stylus/mcp