Design a PCB on your phone.

Circuitcaster is a touch-first PCB design tool for phones and tablets. Ideas hit you when they hit you — the tool should be there when they do. Open Chrome or Safari, start designing. No app install, no signup, no wall.

Why phone PCB design

Every serious hobbyist and engineer has had the same experience: you're on the couch, at a coffee shop, in a coworker's office, and an idea for a small circuit clicks. You reach for your phone, then remember — the design tool is on your desktop. By the time you're back at your desk, the shape of the idea has faded.

Circuitcaster inverts that. The design tool is on your phone. When the idea hits, you sketch it. When you're at your desk later, you finish it. Same project, both devices, no export dance.

How it feels on a phone

• Dot grid at natural pitch — 2.54mm (0.1 inch) by default. Pads snap to dots. Sub-grid nudge for offset placement.
• Touch-native gestures — tap to place, long-press to bend a wire, pinch to zoom, drag to pan. No hover-only tricks.
• S Pen and Apple Pencil support — precise placement feels FASTER than a mouse for most designers.
• 1:1 print mode — hold your phone against the actual chip's printed footprint to verify pin placement before you commit.
• The whole UI scales — the same views work on a 5-inch phone, a 12-inch tablet, or a 32-inch desktop.

Cross-device workflow

QR-code device linking bridges phone and desktop. Start on your phone, scan a QR from another device, keep going. All projects sync across your linked devices.

Powered by an AI-native architecture

Circuitcaster's core innovation is machine-readable design. The site hosts a manual for AIs at /llms.txt, and the running app exposes a JavaScript API any browser-driving AI can call. Which means: even on your phone, you can prompt an AI (Claude in Chrome, Gemini in Chrome) to draft the schematic while you review it. Human + AI collaboration on a phone. Nobody's done that for PCBs.

Learn how AIs drive Circuitcaster →

Frequently asked questions