diff --git a/NucleicRemote/NucleicRemote/Views/PairingScannerView.swift b/NucleicRemote/NucleicRemote/Views/PairingScannerView.swift
index 5ae082f..77aafa4 100644
--- a/NucleicRemote/NucleicRemote/Views/PairingScannerView.swift
+++ b/NucleicRemote/NucleicRemote/Views/PairingScannerView.swift
@@ -2,34 +2,39 @@ import SwiftUI
 import AVFoundation
 import NucleicProtocol
 
+/// Why the live camera feed isn't showing, so the scanner never sits on a silent black screen.
+enum ScannerCameraState: Equatable {
+    case scanning          // feed is live
+    case denied            // permission off — needs Settings
+    case unavailable       // no camera on this device (e.g. the Simulator)
+}
+
 /// Camera QR scanner (UX_IOS §7). Decodes the Mac's `nucleic://pair?d=…` QR into a
 /// `PairingPayload` and hands it back exactly once.
 struct PairingScannerView: View {
     let onScanned: (PairingPayload) -> Void
     @Environment(\.dismiss) private var dismiss
     @State private var error: String?
+    @State private var cameraState: ScannerCameraState = .scanning
 
     var body: some View {
         NavigationStack {
             ZStack {
-                QRScannerRepresentable { value in handle(value) }
+                Color.black.ignoresSafeArea()
+                QRScannerRepresentable(onFound: handle, onState: { cameraState = $0 })
                     .ignoresSafeArea()
                 VStack {
                     Spacer()
-                    RoundedRectangle(cornerRadius: 16)
-                        .stroke(.white.opacity(0.8), lineWidth: 3)
-                        .frame(width: 240, height: 240)
-                    Spacer()
-                    if let error {
-                        Text(error).foregroundStyle(.white)
-                            .padding().background(.red.opacity(0.8), in: Capsule())
-                    } else {
-                        Text("Point at the QR code on your Mac")
-                            .foregroundStyle(.white)
-                            .padding().background(.black.opacity(0.5), in: Capsule())
+                    if cameraState == .scanning {
+                        RoundedRectangle(cornerRadius: 16)
+                            .stroke(.white.opacity(0.8), lineWidth: 3)
+                            .frame(width: 240, height: 240)
                     }
+                    Spacer()
+                    statusBanner
                     Spacer().frame(height: 40)
                 }
+                .padding(.horizontal, 24)
             }
             .navigationTitle("Scan to pair")
             .navigationBarTitleDisplayMode(.inline)
@@ -37,6 +42,41 @@ struct PairingScannerView: View {
         }
     }
 
+    @ViewBuilder
+    private var statusBanner: some View {
+        if let error {
+            banner(error, tint: .red.opacity(0.85))
+        } else {
+            switch cameraState {
+            case .scanning:
+                banner("Point at the QR code on your Mac", tint: .black.opacity(0.5))
+            case .unavailable:
+                VStack(spacing: 12) {
+                    banner("The camera isn't available here — pairing needs a real iPhone, not the Simulator.",
+                           tint: .black.opacity(0.6))
+                }
+            case .denied:
+                VStack(spacing: 12) {
+                    banner("Camera access is off. Enable it to scan the pairing code.", tint: .black.opacity(0.6))
+                    Button("Open Settings") {
+                        if let url = URL(string: UIApplication.openSettingsURLString) {
+                            UIApplication.shared.open(url)
+                        }
+                    }
+                    .buttonStyle(.borderedProminent)
+                }
+            }
+        }
+    }
+
+    private func banner(_ text: String, tint: Color) -> some View {
+        Text(text)
+            .multilineTextAlignment(.center)
+            .foregroundStyle(.white)
+            .padding(.horizontal, 16).padding(.vertical, 10)
+            .background(tint, in: RoundedRectangle(cornerRadius: 16))
+    }
+
     private func handle(_ value: String) {
         guard let payload = try? PairingPayload(qrString: value) else {
             error = "That isn't a Nucleic pairing code"; return
@@ -48,10 +88,12 @@ struct PairingScannerView: View {
 /// UIKit bridge for the AVCaptureSession metadata scan.
 struct QRScannerRepresentable: UIViewControllerRepresentable {
     let onFound: (String) -> Void
+    let onState: (ScannerCameraState) -> Void
 
     func makeUIViewController(context: Context) -> QRScannerController {
         let controller = QRScannerController()
         controller.onFound = onFound
+        controller.onState = onState
         return controller
     }
     func updateUIViewController(_ controller: QRScannerController, context: Context) {}
@@ -59,18 +101,45 @@ struct QRScannerRepresentable: UIViewControllerRepresentable {
 
 final class QRScannerController: UIViewController, AVCaptureMetadataOutputObjectsDelegate {
     var onFound: ((String) -> Void)?
+    var onState: ((ScannerCameraState) -> Void)?
     private let session = AVCaptureSession()
+    private let sessionQueue = DispatchQueue(label: "nucleic.qrscanner.session")
+    private var preview: AVCaptureVideoPreviewLayer?
     private var didFind = false
 
     override func viewDidLoad() {
         super.viewDidLoad()
+        view.backgroundColor = .black
+        // Gate on camera authorization first — without this the prompt may never appear and the
+        // feed silently fails (and on a denied device it would just stay black).
+        switch AVCaptureDevice.authorizationStatus(for: .video) {
+        case .authorized:
+            configureSession()
+        case .notDetermined:
+            AVCaptureDevice.requestAccess(for: .video) { [weak self] granted in
+                DispatchQueue.main.async {
+                    granted ? self?.configureSession() : self?.report(.denied)
+                }
+            }
+        case .denied, .restricted:
+            report(.denied)
+        @unknown default:
+            report(.denied)
+        }
+    }
+
+    /// Build the capture graph. Reports `.unavailable` when there's no camera (the Simulator) so
+    /// the UI can explain the black screen instead of leaving the user guessing.
+    private func configureSession() {
         guard let device = AVCaptureDevice.default(for: .video),
               let input = try? AVCaptureDeviceInput(device: device),
-              session.canAddInput(input) else { return }
+              session.canAddInput(input) else {
+            report(.unavailable); return
+        }
         session.addInput(input)
 
         let output = AVCaptureMetadataOutput()
-        guard session.canAddOutput(output) else { return }
+        guard session.canAddOutput(output) else { report(.unavailable); return }
         session.addOutput(output)
         output.setMetadataObjectsDelegate(self, queue: .main)
         output.metadataObjectTypes = [.qr]
@@ -79,13 +148,26 @@ final class QRScannerController: UIViewController, AVCaptureMetadataOutputObject
         preview.videoGravity = .resizeAspectFill
         preview.frame = view.layer.bounds
         view.layer.addSublayer(preview)
+        self.preview = preview
 
-        Task.detached { [session] in session.startRunning() }
+        report(.scanning)
+        sessionQueue.async { [session] in session.startRunning() }
+    }
+
+    override func viewDidLayoutSubviews() {
+        super.viewDidLayoutSubviews()
+        // Keep the preview filling the view across layout/rotation (setting it once in viewDidLoad
+        // left it mis-sized when bounds weren't final yet).
+        preview?.frame = view.layer.bounds
     }
 
     override func viewDidDisappear(_ animated: Bool) {
         super.viewDidDisappear(animated)
-        session.stopRunning()
+        sessionQueue.async { [session] in session.stopRunning() }
+    }
+
+    private func report(_ state: ScannerCameraState) {
+        onState?(state)
     }
 
     func metadataOutput(