diff --git a/CLAUDE.md b/CLAUDE.md
index d3f3319..59028b5 100644
--- a/CLAUDE.md
+++ b/CLAUDE.md
@@ -9,18 +9,19 @@ A native macOS app that shows video from a capture device (camera / capture card
 - Optional start in full screen. On by default, choice is remembered.
 - Localization: English and Polish (`Resources/{en,pl}.lproj`), following the system language.
 - Extras: per-device format (resolution/FPS), scaling modes (fit/fill/stretch), always on top, mute (⇧⌘M), Window menu (system tiling, full screen ⌃⌘F), automatic resume when a device is unplugged/replugged.
+- Autostart menu: launch the app when a chosen USB device is attached (`Sources/Autostart.swift`, per-user LaunchAgent with an IOKit match on USB vendor/product ID parsed from `AVCaptureDevice.modelID`). `uninstall.sh` must remove the agent.
 - Out of scope (for now): launch at login, recording, screenshots, volume slider.
 
 ## Structure
 - `Sources/` – app code (AppKit + AVFoundation, one `AVCaptureSession`, audio via `AVCaptureAudioPreviewOutput`). The `App` class is split into extensions:
-  `main.swift` (entry point), `App.swift` (state, window, lifecycle), `Capture.swift` (devices, formats, hot-plug), `Menu.swift` (menus and actions), `Power.swift` (sleep prevention), `Preferences.swift` (UserDefaults-backed settings).
+  `main.swift` (entry point), `App.swift` (state, window, lifecycle), `Capture.swift` (devices, formats, hot-plug), `Menu.swift` (menus and actions), `Power.swift` (sleep prevention), `Autostart.swift` (launch-on-connect agent), `Preferences.swift` (UserDefaults-backed settings).
 - `Config/Info.plist`, `Config/SecondDisplay.entitlements`, `Config/dmg/` – version, permissions (camera, microphone; hardened runtime).
 - `Resources/` – `AppIcon.icon` (Icon Composer, Liquid Glass; compiled by `actool`), `{en,pl}.lproj` (`Localizable.strings`, `InfoPlist.strings`), `uninstall.sh` (copied into the bundle; removes the app, preferences, caches, TCC permissions). Bundle ID: `com.mmacierzanka.seconddisplay`.
 - `scripts/check-strings.sh` – en/pl translation consistency. `scripts/make-dmg-background.swift` regenerates `Config/dmg/background.png`; keep its size and icon coordinates in sync with `Config/dmg/settings.py` (dmgbuild layout, installed into `build/venv` on first `make dmg`).
 - `Makefile` – `make` (builds `build/SecondDisplay.app`), `run`, `check`, `install`, `uninstall`, `dmg`, `clean`, `help`. Builds are universal (arm64 + x86_64, macOS 26+). `make dmg` makes an un-notarized DMG with `Config/dmg/Read Me First.txt`. `SIGN_ID` defaults to ad-hoc (`-`).
 
 ## Conventions
-- Settings live in `UserDefaults` (keys: `video`, `audio`, `keepAwake`, `startFull`, `onTop`, `gravity`, `format.<id>`).
+- Settings live in `UserDefaults` (keys: `video`, `audio`, `autostart`, `autostartName`, `keepAwake`, `startFull`, `onTop`, `gravity`, `format.<id>`).
 - Add new strings through `NSLocalizedString` and to both `Localizable.strings` files.
 - Run `make check` before committing. Version is in `Config/Info.plist`; build number = commit count.
 - Commits: small, one per feature, with a `Co-Authored-By` line.
diff --git a/README.md b/README.md
index 9233629..3405c1a 100644
--- a/README.md
+++ b/README.md
@@ -34,6 +34,8 @@ If you received a prebuilt copy (the `.dmg`), drag the app to Applications. It i
 ## Usage
 Menus at the top of the screen: **Video** (device, format), **Audio** (source or off), **Options** (prevent display sleep, start in full screen, always on top, mute ⇧⌘M, scaling), **Window** (tiling, full screen ⌃⌘F).
 
+**Autostart** opens the app whenever the chosen USB capture device is plugged in (and makes it the active video source). It installs a per-user LaunchAgent (`~/Library/LaunchAgents/com.mmacierzanka.seconddisplay.autostart.plist`) matching the device's USB vendor/product ID, so only USB (UVC) devices can be chosen. Choose **Off** to remove it; the uninstall script removes it too.
+
 ## Layout
 - `Sources/` – the app (AppKit + AVFoundation): `App` (state, window), `Capture` (devices, formats), `Menu`, `Power`, `Preferences`, `main` (entry point)
 - `Config/` – `Info.plist`, entitlements (camera, microphone), `dmg/` (instructions shipped in the disk image)
diff --git a/Resources/en.lproj/Localizable.strings b/Resources/en.lproj/Localizable.strings
index 90f2ed3..87a1cb5 100644
--- a/Resources/en.lproj/Localizable.strings
+++ b/Resources/en.lproj/Localizable.strings
@@ -20,3 +20,5 @@
 "Bring All to Front" = "Bring All to Front";
 "No capture devices found" = "No capture devices found";
 "Connect a camera or capture card and launch Second Display again." = "Connect a camera or capture card and launch Second Display again.";
+"Autostart" = "Autostart";
+"(not connected)" = "(not connected)";
diff --git a/Resources/pl.lproj/Localizable.strings b/Resources/pl.lproj/Localizable.strings
index 5ac5464..e9f560f 100644
--- a/Resources/pl.lproj/Localizable.strings
+++ b/Resources/pl.lproj/Localizable.strings
@@ -20,3 +20,5 @@
 "Bring All to Front" = "Przenieś wszystko na wierzch";
 "No capture devices found" = "Nie znaleziono urządzeń przechwytujących";
 "Connect a camera or capture card and launch Second Display again." = "Podłącz kamerę lub urządzenie przechwytujące i uruchom Second Display ponownie.";
+"Autostart" = "Autostart";
+"(not connected)" = "(niepodłączone)";
diff --git a/Resources/uninstall.sh b/Resources/uninstall.sh
index 4c155d9..aaa18f7 100755
--- a/Resources/uninstall.sh
+++ b/Resources/uninstall.sh
@@ -6,6 +6,8 @@ APP="${0:A:h:h:h}"
 read -q "?Delete $APP and all its data? [y/N] " || { echo; echo Cancelled; exit 0; }
 echo
 pkill -x SecondDisplay 2>/dev/null
+launchctl bootout "gui/$(id -u)/$ID.autostart" 2>/dev/null   # launch-on-connect agent
+rm -f ~/Library/LaunchAgents/$ID.autostart.plist
 defaults delete "$ID" 2>/dev/null
 tccutil reset All "$ID" >/dev/null 2>&1   # camera / microphone permissions
 L=~/Library
diff --git a/Sources/App.swift b/Sources/App.swift
index 7c00c97..c0b384a 100644
--- a/Sources/App.swift
+++ b/Sources/App.swift
@@ -8,7 +8,7 @@ final class App: NSObject, NSApplicationDelegate {
     var videoInput: AVCaptureDeviceInput?
     var audioInput: AVCaptureDeviceInput?
     var window: NSWindow!
-    let videoMenu = NSMenu(), audioMenu = NSMenu(), optionsMenu = NSMenu(), windowMenu = NSMenu()
+    let videoMenu = NSMenu(), audioMenu = NSMenu(), optionsMenu = NSMenu(), windowMenu = NSMenu(), autostartMenu = NSMenu()
     var sleepAssertion: IOPMAssertionID = 0
     var keepAwake = false
     var layer: AVCaptureVideoPreviewLayer!
diff --git a/Sources/Autostart.swift b/Sources/Autostart.swift
new file mode 100644
index 0000000..434fca7
--- /dev/null
+++ b/Sources/Autostart.swift
@@ -0,0 +1,72 @@
+import AppKit
+import AVFoundation
+
+// Launch-on-connect: a per-user LaunchAgent that opens the app when the chosen USB device is attached.
+extension App {
+    static let agentLabel = "com.mmacierzanka.seconddisplay.autostart"
+    var agentURL: URL {
+        FileManager.default.homeDirectoryForCurrentUser.appendingPathComponent("Library/LaunchAgents/\(Self.agentLabel).plist")
+    }
+    var autostartID: String? { defaults.string(forKey: "autostart") }
+
+    // UVC cameras report e.g. "UVC Camera VendorID_21325 ProductID_8457" (decimal); other devices have no USB ids.
+    func usbIDs(_ d: AVCaptureDevice) -> (vendor: Int, product: Int)? {
+        func number(after key: String) -> Int? {
+            guard let r = d.modelID.range(of: key) else { return nil }
+            return Int(d.modelID[r.upperBound...].prefix(while: \.isNumber))
+        }
+        guard let v = number(after: "VendorID_"), let p = number(after: "ProductID_") else { return nil }
+        return (v, p)
+    }
+
+    func launchctl(_ args: String...) {
+        let p = Process()
+        p.executableURL = URL(fileURLWithPath: "/bin/launchctl")
+        p.arguments = args
+        p.standardError = FileHandle.nullDevice
+        try? p.run(); p.waitUntilExit()
+    }
+
+    func setAutostart(_ d: AVCaptureDevice?) {
+        let domain = "gui/\(getuid())"
+        launchctl("bootout", "\(domain)/\(Self.agentLabel)")
+        guard let d = d, let ids = usbIDs(d) else {
+            try? FileManager.default.removeItem(at: agentURL)
+            defaults.removeObject(forKey: "autostart"); defaults.removeObject(forKey: "autostartName")
+            return
+        }
+        let plist: [String: Any] = [
+            "Label": Self.agentLabel,
+            "ProgramArguments": ["/usr/bin/open", Bundle.main.bundlePath],
+            "LaunchEvents": ["com.apple.iokit.matching": ["attach": [
+                "IOProviderClass": "IOUSBHostDevice", "idVendor": ids.vendor, "idProduct": ids.product, "IOMatchLaunchStream": true]]],
+        ]
+        guard let data = try? PropertyListSerialization.data(fromPropertyList: plist, format: .xml, options: 0) else { return }
+        try? FileManager.default.createDirectory(at: agentURL.deletingLastPathComponent(), withIntermediateDirectories: true)
+        try? data.write(to: agentURL)
+        defaults.set(d.uniqueID, forKey: "autostart"); defaults.set(d.localizedName, forKey: "autostartName")
+        launchctl("bootstrap", domain, agentURL.path)  // fires at once if the device is already attached
+    }
+
+    @objc func pickAutostart(_ s: NSMenuItem) { setAutostart(s.representedObject as? AVCaptureDevice) }
+
+    func fillAutostartMenu(_ menu: NSMenu) {
+        menu.removeAllItems()
+        let off = NSMenuItem(title: NSLocalizedString("Off", comment: ""), action: #selector(pickAutostart(_:)), keyEquivalent: "")
+        off.target = self; off.state = autostartID == nil ? .on : .off
+        menu.addItem(off)
+        menu.addItem(.separator())
+        let devices = videoDevices()
+        for d in devices {
+            let it = NSMenuItem(title: d.localizedName, action: usbIDs(d) == nil ? nil : #selector(pickAutostart(_:)), keyEquivalent: "")
+            it.target = self; it.representedObject = d
+            it.state = d.uniqueID == autostartID ? .on : .off
+            menu.addItem(it)
+        }
+        if let id = autostartID, !devices.contains(where: { $0.uniqueID == id }) {
+            let it = NSMenuItem(title: "\(defaults.string(forKey: "autostartName") ?? id) \(NSLocalizedString("(not connected)", comment: ""))", action: nil, keyEquivalent: "")
+            it.state = .on
+            menu.addItem(it)
+        }
+    }
+}
diff --git a/Sources/Capture.swift b/Sources/Capture.swift
index 09ae12b..865936f 100644
--- a/Sources/Capture.swift
+++ b/Sources/Capture.swift
@@ -4,7 +4,11 @@ import AVFoundation
 extension App {
     func observeDevices() {
         let nc = NotificationCenter.default
-        nc.addObserver(forName: AVCaptureDevice.wasConnectedNotification, object: nil, queue: .main) { _ in self.restore() }
+        nc.addObserver(forName: AVCaptureDevice.wasConnectedNotification, object: nil, queue: .main) { n in
+            // the autostart device takes over the picture as soon as it appears
+            if let d = n.object as? AVCaptureDevice, d.hasMediaType(.video), d.uniqueID == self.autostartID { self.setVideo(d) }
+            self.restore()
+        }
         nc.addObserver(forName: AVCaptureDevice.wasDisconnectedNotification, object: nil, queue: .main) { n in
             guard let d = n.object as? AVCaptureDevice else { return }
             if d.uniqueID == self.videoInput?.device.uniqueID { self.swap(&self.videoInput, to: nil) }
@@ -35,9 +39,9 @@ extension App {
 
     func restore() {
         if videoInput == nil {
-            if let id = defaults.string(forKey: "video"), let d = videoDevices().first(where: { $0.uniqueID == id }) {
-                setVideo(d)
-            } else if let d = videoDevices().first { setVideo(d) }
+            let devices = videoDevices()
+            let preferred = [autostartID, defaults.string(forKey: "video")].compactMap { id in devices.first { $0.uniqueID == id } }
+            if let d = preferred.first ?? devices.first { setVideo(d) }
         }
         if audioInput == nil, let id = defaults.string(forKey: "audio"), let d = audioDevices().first(where: { $0.uniqueID == id }) {
             setAudio(d)
diff --git a/Sources/Menu.swift b/Sources/Menu.swift
index 2ea5cec..ad1a635 100644
--- a/Sources/Menu.swift
+++ b/Sources/Menu.swift
@@ -6,7 +6,7 @@ extension App: NSMenuDelegate {
         let main = NSMenu()
         let appMenu = NSMenu()
         appMenu.addItem(NSMenuItem(title: NSLocalizedString("Quit Second Display", comment: ""), action: #selector(NSApplication.terminate(_:)), keyEquivalent: "q"))
-        for (title, sub) in [("", appMenu), (NSLocalizedString("Video", comment: ""), videoMenu), (NSLocalizedString("Audio", comment: ""), audioMenu), (NSLocalizedString("Options", comment: ""), optionsMenu), (NSLocalizedString("Window", comment: ""), windowMenu)] {
+        for (title, sub) in [("", appMenu), (NSLocalizedString("Video", comment: ""), videoMenu), (NSLocalizedString("Audio", comment: ""), audioMenu), (NSLocalizedString("Autostart", comment: ""), autostartMenu), (NSLocalizedString("Options", comment: ""), optionsMenu), (NSLocalizedString("Window", comment: ""), windowMenu)] {
             let item = NSMenuItem(title: title, action: nil, keyEquivalent: "")
             sub.title = title; sub.delegate = self; item.submenu = sub
             main.addItem(item)
@@ -56,6 +56,8 @@ extension App: NSMenuDelegate {
                 it.state = d.uniqueID == audioInput?.device.uniqueID ? .on : .off
                 menu.addItem(it)
             }
+        } else if menu === autostartMenu {
+            fillAutostartMenu(menu)
         } else if menu === optionsMenu {
             menu.removeAllItems()
             let k = NSMenuItem(title: NSLocalizedString("Prevent display sleep", comment: ""), action: #selector(toggleAwake), keyEquivalent: "")