SimulatorCamera

Your Mac's camera, in the iOS Simulator. Free and open.

The iOS Simulator has never had a real camera. AVCaptureDevice returns nil. Every app that touches the camera — QR scanners, barcode readers, document capture, ML pipelines, AR prototypes, video calling — either stubs the camera path, runs only on physical devices, or ships a brittle "use a photo instead" fallback.

SimulatorCamera registers a virtual camera at the macOS system level using Apple's CMIOExtension API. The iOS Simulator (Xcode 16+) sees the virtual camera through standard AVFoundation. Your existing AVCaptureSession code Just Works. Zero SDK integration. Zero Info.plist changes. Zero #if targetEnvironment(simulator) branches.

What you get

• 🎥 Mac webcam → iOS Simulator — your existing app sees frames at 30 FPS, 1280×720
• 🎬 Video file source — drop in any MP4 / MOV / HEVC, loops cleanly
• 🖼 Static image source — pick a PNG / JPG, becomes the camera feed
• 🔲 QR code generator — programmatic QR for scanner testing
• 🌈 Test pattern — built-in colorbar / scrolling stripe, always available
• 🤖 simcamctl CLI — simcamctl set-source --qr "TOKEN" for CI / AI agents
• 🛡 Zero SDK — your iOS app code does not import or link anything from this project
• 📵 Zero device required — runs entirely in the iOS Simulator
• 🆓 Free, MIT-licensed, open source — fork it, ship it, sell it, no fees

Demo

[hero GIF lands here in v1.0.0 release]

Install

Status: pre-release. Build from source. There is no published binary, no Homebrew cask, and no App Store listing yet. Distribution is still being decided — macOS system extensions have real constraints on how they can be shipped to the public. For now you build and sign it yourself with your own Apple developer account.

1. Build the Mac companion app.

Requires macOS 14+, Xcode 16+, and XcodeGen (brew install xcodegen):

git clone https://github.com/dautovri/SimulatorCamera.git
cd SimulatorCamera
xcodegen generate
open SimulatorCamera.xcodeproj

In Xcode, set your own signing team on both the SimulatorCamera and SimulatorCameraExtension targets, then build.

2. Move the built app to /Applications and launch it.

macOS refuses to activate a system extension from anywhere else — running straight from Xcode's build directory will fail.

3. Click Activate, then approve when System Settings prompts.

Approval lives in System Settings → General → Login Items & Extensions, and is needed once per machine.

That's it. No Xcode integration, no Info.plist changes, no #if guards anywhere in your consuming app's code.

Not a Swift Package. SimulatorCamera has no Package.swift and cannot be added via SPM, CocoaPods, or Carthage — on purpose. It's a macOS system extension (Apple's CMIOExtension API), not a library your app links. Install the Mac companion app with the brew command above; your iOS app imports and links nothing from this project.

3. Run any iOS Simulator app that uses the camera. Open it in Xcode 16+, run on a Simulator, and AVCaptureDevice.default(for: .video) returns "SimulatorCamera Virtual."

// This — yes, exactly this — works in the iOS Simulator now:
let session = AVCaptureSession()
let device = AVCaptureDevice.default(for: .video)!
let input = try AVCaptureDeviceInput(device: device)
session.addInput(input)
session.startRunning()
// frames flow through your existing AVCaptureVideoDataOutput delegates

Picking a source

Open the SimulatorCamera Mac app:

Source	Use case
Test Pattern	Default. Confirms wiring works. No permissions, no setup.
Mac Camera	Live webcam (built-in or external). First use prompts for camera access.
Video File	Pre-recorded scenarios. Loops at EOF. Honors orientation metadata.
Static Image	Pin a frame for visual UI tests. Same image, fresh timestamps.
QR Code	Programmatic QR for scanner / payment-flow tests.

Driving from the command line

simcamctl is bundled with the app and can be symlinked into $PATH:

ln -s /Applications/SimulatorCamera.app/Contents/MacOS/simcamctl /usr/local/bin/simcamctl

simcamctl ping
# extension pid=12345 bundle=com.dautov.SimulatorCamera.Extension

simcamctl set-source --qr "https://example.com/auth?token=ABC123"
# QR pushed (40 chars, 3686 KB)

simcamctl set-source --image ./test-fixtures/receipt.png
# image pushed: receipt.png (1280x720)

simcamctl status
# active source:    QR code
# connected clients:1
# last frame ts:    1714159823.412s
# stream running:   yes

Useful for:

• CI scripts that run xcodebuild test against scanner / vision flows
• AI agents that need to feed deterministic test fixtures into UI tests
• Manual QA scripts that walk through simcamctl set-source --image fixture-N.png

React Native / Expo / WebRTC apps

Some popular libraries hard-code #if targetEnvironment(simulator) to disable camera entirely. With SimulatorCamera the simulator does have a camera, so those guards prevent the virtual feed from reaching your app.

We ship patch-package-compatible patches for known libraries:

Library	Versions that may need patching	Patch
expo-camera	<55.0.11	patches/expo-camera/
react-native-vision-camera	<5.0	patches/react-native-vision-camera/
react-native-webrtc	all	patches/react-native-webrtc/
@fishjam-cloud/react-native-webrtc	all	patches/fishjam-react-native-webrtc/

Architecture

SimulatorCamera.app  (container)
   ↓ XPC
.app/Contents/Library/SystemExtensions/
   SimulatorCameraExtension.systemextension
   ↓ CMIOExtensionStream.send
macOS CoreMediaIO subsystem
   ↓ host AVFoundation
iOS Simulator process
   ↓ AVCaptureDevice.default(for: .video)
   "SimulatorCamera Virtual"  ← your app

Full diagrams in docs/ARCHITECTURE.md.

Why this exists

Software Mansion shipped SimCam in March 2026 — the same architecture as a polished commercial product ($19 lifetime). SimulatorCamera is the free, open-source alternative for people who'd rather pay $0 and have the source. Both projects exist because Apple has not (yet) shipped first-party simulator camera support; both rely on Apple's public CMIOExtension API.

If you're after polished commercial support, buy SimCam — Software Mansion deserves it. If you'd rather contribute fixes back instead of opening tickets, you're in the right repo.

Roadmap

This is Act 1 of the iOS Simulator's missing sensor layer.

• v1.0 (now) — virtual camera, 5 sources, CLI, library patches
• v1.1 — IOSurface zero-copy frames (1080p/60fps), front/back camera switch, video pause/scrub
• v1.2 — scenario DSL: simcamctl scenario play receipt-then-qr.json for xcodebuild test integration
• v2.0 — microphone passthrough (same architecture, different sensor)
• vN — BLE peripheral simulation, motion sensors, LiDAR — every sensor the iPhone has, simulated

Contributing

See CONTRIBUTING.md. Good first issues are labelled on the tracker. For release mechanics, see RELEASING.md.

Sponsor

SimulatorCamera is fully MIT-licensed and maintained on donations. If it saves you a device-build loop, consider sponsoring or buying a coffee.

License

MIT — see LICENSE.