wireless camera app for Android

Stream a phone's camera to a tablet over WiFi/hotspot. WebSocket transport with native YUV-to-JPEG encoding, UDP auto-discovery, remote control (zoom, flash, camera switch, rotate, mirror) from the viewer.
2026-03-06 18:14:27 +00:00
commit 1660696d7f
32 changed files with 1962 additions and 0 deletions
--- a/.gitignore
+++ b/.gitignore
@@ -0,0 +1,45 @@
+# Miscellaneous
+*.class
+*.log
+*.pyc
+*.swp
+.DS_Store
+.atom/
+.build/
+.buildlog/
+.history
+.svn/
+.swiftpm/
+migrate_working_dir/
+
+# IntelliJ related
+*.iml
+*.ipr
+*.iws
+.idea/
+
+# The .vscode folder contains launch configuration and tasks you configure in
+# VS Code which you may wish to be included in version control, so this line
+# is commented out by default.
+#.vscode/
+
+# Flutter/Dart/Pub related
+**/doc/api/
+**/ios/Flutter/.last_build_id
+.dart_tool/
+.flutter-plugins-dependencies
+.pub-cache/
+.pub/
+/build/
+/coverage/
+
+# Symbolication related
+app.*.symbols
+
+# Obfuscation related
+app.*.map.json
+
+# Android Studio will place build artifacts here
+/android/app/debug
+/android/app/profile
+/android/app/release
--- a/.metadata
+++ b/.metadata
@@ -0,0 +1,30 @@
+# This file tracks properties of this Flutter project.
+# Used by Flutter tool to assess capabilities and perform upgrades etc.
+#
+# This file should be version controlled and should not be manually edited.
+
+version:
+  revision: "44a626f4f0027bc38a46dc68aed5964b05a83c18"
+  channel: "stable"
+
+project_type: app
+
+# Tracks metadata for the flutter migrate command
+migration:
+  platforms:
+    - platform: root
+      create_revision: 44a626f4f0027bc38a46dc68aed5964b05a83c18
+      base_revision: 44a626f4f0027bc38a46dc68aed5964b05a83c18
+    - platform: android
+      create_revision: 44a626f4f0027bc38a46dc68aed5964b05a83c18
+      base_revision: 44a626f4f0027bc38a46dc68aed5964b05a83c18
+
+  # User provided section
+
+  # List of Local paths (relative to this file) that should be
+  # ignored by the migrate tool.
+  #
+  # Files that are not part of the templates will be ignored by default.
+  unmanaged_files:
+    - 'lib/main.dart'
+    - 'ios/Runner.xcodeproj/project.pbxproj'
--- a/README.md
+++ b/README.md
@@ -0,0 +1,17 @@
+# external_cam
+
+A new Flutter project.
+
+## Getting Started
+
+This project is a starting point for a Flutter application.
+
+A few resources to get you started if this is your first Flutter project:
+
+- [Learn Flutter](https://docs.flutter.dev/get-started/learn-flutter)
+- [Write your first Flutter app](https://docs.flutter.dev/get-started/codelab)
+- [Flutter learning resources](https://docs.flutter.dev/reference/learning-resources)
+
+For help getting started with Flutter development, view the
+[online documentation](https://docs.flutter.dev/), which offers tutorials,
+samples, guidance on mobile development, and a full API reference.
--- a/analysis_options.yaml
+++ b/analysis_options.yaml
@@ -0,0 +1,28 @@
+# This file configures the analyzer, which statically analyzes Dart code to
+# check for errors, warnings, and lints.
+#
+# The issues identified by the analyzer are surfaced in the UI of Dart-enabled
+# IDEs (https://dart.dev/tools#ides-and-editors). The analyzer can also be
+# invoked from the command line by running `flutter analyze`.
+
+# The following line activates a set of recommended lints for Flutter apps,
+# packages, and plugins designed to encourage good coding practices.
+include: package:flutter_lints/flutter.yaml
+
+linter:
+  # The lint rules applied to this project can be customized in the
+  # section below to disable rules from the `package:flutter_lints/flutter.yaml`
+  # included above or to enable additional rules. A list of all available lints
+  # and their documentation is published at https://dart.dev/lints.
+  #
+  # Instead of disabling a lint rule for the entire project in the
+  # section below, it can also be suppressed for a single line of code
+  # or a specific dart file by using the `// ignore: name_of_lint` and
+  # `// ignore_for_file: name_of_lint` syntax on the line or in the file
+  # producing the lint.
+  rules:
+    # avoid_print: false  # Uncomment to disable the `avoid_print` rule
+    # prefer_single_quotes: true  # Uncomment to enable the `prefer_single_quotes` rule
+
+# Additional information about this file can be found at
+# https://dart.dev/guides/language/analysis-options
--- a/android/.gitignore
+++ b/android/.gitignore
@@ -0,0 +1,14 @@
+gradle-wrapper.jar
+/.gradle
+/captures/
+/gradlew
+/gradlew.bat
+/local.properties
+GeneratedPluginRegistrant.java
+.cxx/
+
+# Remember to never publicly share your keystore.
+# See https://flutter.dev/to/reference-keystore
+key.properties
+**/*.keystore
+**/*.jks
--- a/android/app/build.gradle.kts
+++ b/android/app/build.gradle.kts
@@ -0,0 +1,44 @@
+plugins {
+    id("com.android.application")
+    id("kotlin-android")
+    // The Flutter Gradle Plugin must be applied after the Android and Kotlin Gradle plugins.
+    id("dev.flutter.flutter-gradle-plugin")
+}
+
+android {
+    namespace = "com.kschappell.external_cam"
+    compileSdk = flutter.compileSdkVersion
+    ndkVersion = flutter.ndkVersion
+
+    compileOptions {
+        sourceCompatibility = JavaVersion.VERSION_17
+        targetCompatibility = JavaVersion.VERSION_17
+    }
+
+    kotlinOptions {
+        jvmTarget = JavaVersion.VERSION_17.toString()
+    }
+
+    defaultConfig {
+        // TODO: Specify your own unique Application ID (https://developer.android.com/studio/build/application-id.html).
+        applicationId = "com.kschappell.external_cam"
+        // You can update the following values to match your application needs.
+        // For more information, see: https://flutter.dev/to/review-gradle-config.
+        minSdk = flutter.minSdkVersion
+        targetSdk = flutter.targetSdkVersion
+        versionCode = flutter.versionCode
+        versionName = flutter.versionName
+    }
+
+    buildTypes {
+        release {
+            // TODO: Add your own signing config for the release build.
+            // Signing with the debug keys for now, so `flutter run --release` works.
+            signingConfig = signingConfigs.getByName("debug")
+        }
+    }
+}
+
+flutter {
+    source = "../.."
+}
--- a/android/app/src/debug/AndroidManifest.xml
+++ b/android/app/src/debug/AndroidManifest.xml
@@ -0,0 +1,7 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <!-- The INTERNET permission is required for development. Specifically,
+         the Flutter tool needs it to communicate with the running application
+         to allow setting breakpoints, to provide hot reload, etc.
+    -->
+    <uses-permission android:name="android.permission.INTERNET"/>
+</manifest>
--- a/android/app/src/main/AndroidManifest.xml
+++ b/android/app/src/main/AndroidManifest.xml
@@ -0,0 +1,41 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <uses-permission android:name="android.permission.CAMERA" />
+    <uses-permission android:name="android.permission.INTERNET" />
+    <uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />
+    <uses-permission android:name="android.permission.ACCESS_WIFI_STATE" />
+    <uses-permission android:name="android.permission.CHANGE_WIFI_MULTICAST_STATE" />
+
+    <application
+        android:label="External Cam"
+        android:name="${applicationName}"
+        android:icon="@mipmap/ic_launcher"
+        android:usesCleartextTraffic="true">
+        <activity
+            android:name=".MainActivity"
+            android:exported="true"
+            android:launchMode="singleTop"
+            android:taskAffinity=""
+            android:theme="@style/LaunchTheme"
+            android:configChanges="orientation|keyboardHidden|keyboard|screenSize|smallestScreenSize|locale|layoutDirection|fontScale|screenLayout|density|uiMode"
+            android:hardwareAccelerated="true"
+            android:windowSoftInputMode="adjustResize">
+            <meta-data
+              android:name="io.flutter.embedding.android.NormalTheme"
+              android:resource="@style/NormalTheme"
+              />
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN"/>
+                <category android:name="android.intent.category.LAUNCHER"/>
+            </intent-filter>
+        </activity>
+        <meta-data
+            android:name="flutterEmbedding"
+            android:value="2" />
+    </application>
+    <queries>
+        <intent>
+            <action android:name="android.intent.action.PROCESS_TEXT"/>
+            <data android:mimeType="text/plain"/>
+        </intent>
+    </queries>
+</manifest>
--- a/android/app/src/main/kotlin/com/kschappell/external_cam/MainActivity.kt
+++ b/android/app/src/main/kotlin/com/kschappell/external_cam/MainActivity.kt
@@ -0,0 +1,100 @@
+package com.kschappell.external_cam
+
+import android.content.Context
+import android.graphics.ImageFormat
+import android.graphics.Rect
+import android.graphics.YuvImage
+import android.net.wifi.WifiManager
+import io.flutter.embedding.android.FlutterActivity
+import io.flutter.embedding.engine.FlutterEngine
+import io.flutter.plugin.common.MethodChannel
+import java.io.ByteArrayOutputStream
+
+class MainActivity : FlutterActivity() {
+    private var multicastLock: WifiManager.MulticastLock? = null
+
+    override fun configureFlutterEngine(flutterEngine: FlutterEngine) {
+        super.configureFlutterEngine(flutterEngine)
+        acquireMulticastLock()
+
+        MethodChannel(flutterEngine.dartExecutor.binaryMessenger, "com.kschappell.external_cam/jpeg")
+            .setMethodCallHandler { call, result ->
+                if (call.method == "encodeJpeg") {
+                    result.success(
+                        encodeYuvToJpeg(
+                            width = call.argument("width")!!,
+                            height = call.argument("height")!!,
+                            yBuffer = call.argument("y")!!,
+                            uBuffer = call.argument("u")!!,
+                            vBuffer = call.argument("v")!!,
+                            yRowStride = call.argument("yRowStride")!!,
+                            uvRowStride = call.argument("uvRowStride")!!,
+                            uvPixelStride = call.argument("uvPixelStride")!!,
+                            quality = call.argument("quality") ?: 70,
+                        )
+                    )
+                } else {
+                    result.notImplemented()
+                }
+            }
+    }
+
+    private fun acquireMulticastLock() {
+        val wifi = applicationContext.getSystemService(Context.WIFI_SERVICE) as WifiManager
+        multicastLock = wifi.createMulticastLock("external_cam").apply {
+            setReferenceCounted(true)
+            acquire()
+        }
+    }
+
+    override fun onDestroy() {
+        multicastLock?.release()
+        super.onDestroy()
+    }
+
+    private fun encodeYuvToJpeg(
+        width: Int,
+        height: Int,
+        yBuffer: ByteArray,
+        uBuffer: ByteArray,
+        vBuffer: ByteArray,
+        yRowStride: Int,
+        uvRowStride: Int,
+        uvPixelStride: Int,
+        quality: Int,
+    ): ByteArray {
+        val nv21 = ByteArray(width * height * 3 / 2)
+        var pos = 0
+
+        if (yRowStride == width) {
+            System.arraycopy(yBuffer, 0, nv21, 0, width * height)
+            pos = width * height
+        } else {
+            for (row in 0 until height) {
+                System.arraycopy(yBuffer, row * yRowStride, nv21, pos, width)
+                pos += width
+            }
+        }
+
+        val uvHeight = height / 2
+        val uvWidth = width / 2
+        val uvSize = uvWidth * uvHeight * 2
+        if (uvPixelStride == 2 && uvRowStride == width && vBuffer.size >= uvSize) {
+            System.arraycopy(vBuffer, 0, nv21, pos, uvSize)
+        } else {
+            for (row in 0 until uvHeight) {
+                val offset = row * uvRowStride
+                for (col in 0 until uvWidth) {
+                    val uvOffset = offset + col * uvPixelStride
+                    nv21[pos++] = vBuffer[uvOffset]
+                    nv21[pos++] = uBuffer[uvOffset]
+                }
+            }
+        }
+
+        val yuvImage = YuvImage(nv21, ImageFormat.NV21, width, height, null)
+        val stream = ByteArrayOutputStream(width * height / 4)
+        yuvImage.compressToJpeg(Rect(0, 0, width, height), quality, stream)
+        return stream.toByteArray()
+    }
+}
--- a/android/app/src/main/res/drawable-v21/launch_background.xml
+++ b/android/app/src/main/res/drawable-v21/launch_background.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Modify this file to customize your launch splash screen -->
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:drawable="?android:colorBackground" />
+
+    <!-- You can insert your own image assets here -->
+    <!-- <item>
+        <bitmap
+            android:gravity="center"
+            android:src="@mipmap/launch_image" />
+    </item> -->
+</layer-list>
--- a/android/app/src/main/res/drawable/launch_background.xml
+++ b/android/app/src/main/res/drawable/launch_background.xml
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!-- Modify this file to customize your launch splash screen -->
+<layer-list xmlns:android="http://schemas.android.com/apk/res/android">
+    <item android:drawable="@android:color/white" />
+
+    <!-- You can insert your own image assets here -->
+    <!-- <item>
+        <bitmap
+            android:gravity="center"
+            android:src="@mipmap/launch_image" />
+    </item> -->
+</layer-list>
--- a/android/app/src/main/res/mipmap-hdpi/ic_launcher.png
+++ b/android/app/src/main/res/mipmap-hdpi/ic_launcher.png
--- a/android/app/src/main/res/mipmap-mdpi/ic_launcher.png
+++ b/android/app/src/main/res/mipmap-mdpi/ic_launcher.png
--- a/android/app/src/main/res/mipmap-xhdpi/ic_launcher.png
+++ b/android/app/src/main/res/mipmap-xhdpi/ic_launcher.png
--- a/android/app/src/main/res/mipmap-xxhdpi/ic_launcher.png
+++ b/android/app/src/main/res/mipmap-xxhdpi/ic_launcher.png
--- a/android/app/src/main/res/mipmap-xxxhdpi/ic_launcher.png
+++ b/android/app/src/main/res/mipmap-xxxhdpi/ic_launcher.png
--- a/android/app/src/main/res/values-night/styles.xml
+++ b/android/app/src/main/res/values-night/styles.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- Theme applied to the Android Window while the process is starting when the OS's Dark Mode setting is on -->
+    <style name="LaunchTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <!-- Show a splash screen on the activity. Automatically removed when
+             the Flutter engine draws its first frame -->
+        <item name="android:windowBackground">@drawable/launch_background</item>
+    </style>
+    <!-- Theme applied to the Android Window as soon as the process has started.
+         This theme determines the color of the Android Window while your
+         Flutter UI initializes, as well as behind your Flutter UI while its
+         running.
+
+         This Theme is only used starting with V2 of Flutter's Android embedding. -->
+    <style name="NormalTheme" parent="@android:style/Theme.Black.NoTitleBar">
+        <item name="android:windowBackground">?android:colorBackground</item>
+    </style>
+</resources>
--- a/android/app/src/main/res/values/styles.xml
+++ b/android/app/src/main/res/values/styles.xml
@@ -0,0 +1,18 @@
+<?xml version="1.0" encoding="utf-8"?>
+<resources>
+    <!-- Theme applied to the Android Window while the process is starting when the OS's Dark Mode setting is off -->
+    <style name="LaunchTheme" parent="@android:style/Theme.Light.NoTitleBar">
+        <!-- Show a splash screen on the activity. Automatically removed when
+             the Flutter engine draws its first frame -->
+        <item name="android:windowBackground">@drawable/launch_background</item>
+    </style>
+    <!-- Theme applied to the Android Window as soon as the process has started.
+         This theme determines the color of the Android Window while your
+         Flutter UI initializes, as well as behind your Flutter UI while its
+         running.
+
+         This Theme is only used starting with V2 of Flutter's Android embedding. -->
+    <style name="NormalTheme" parent="@android:style/Theme.Light.NoTitleBar">
+        <item name="android:windowBackground">?android:colorBackground</item>
+    </style>
+</resources>
--- a/android/app/src/profile/AndroidManifest.xml
+++ b/android/app/src/profile/AndroidManifest.xml
@@ -0,0 +1,7 @@
+<manifest xmlns:android="http://schemas.android.com/apk/res/android">
+    <!-- The INTERNET permission is required for development. Specifically,
+         the Flutter tool needs it to communicate with the running application
+         to allow setting breakpoints, to provide hot reload, etc.
+    -->
+    <uses-permission android:name="android.permission.INTERNET"/>
+</manifest>
--- a/android/build.gradle.kts
+++ b/android/build.gradle.kts
@@ -0,0 +1,24 @@
+allprojects {
+    repositories {
+        google()
+        mavenCentral()
+    }
+}
+
+val newBuildDir: Directory =
+    rootProject.layout.buildDirectory
+        .dir("../../build")
+        .get()
+rootProject.layout.buildDirectory.value(newBuildDir)
+
+subprojects {
+    val newSubprojectBuildDir: Directory = newBuildDir.dir(project.name)
+    project.layout.buildDirectory.value(newSubprojectBuildDir)
+}
+subprojects {
+    project.evaluationDependsOn(":app")
+}
+
+tasks.register<Delete>("clean") {
+    delete(rootProject.layout.buildDirectory)
+}
--- a/android/gradle.properties
+++ b/android/gradle.properties
@@ -0,0 +1,2 @@
+org.gradle.jvmargs=-Xmx8G -XX:MaxMetaspaceSize=4G -XX:ReservedCodeCacheSize=512m -XX:+HeapDumpOnOutOfMemoryError
+android.useAndroidX=true
--- a/android/gradle/wrapper/gradle-wrapper.properties
+++ b/android/gradle/wrapper/gradle-wrapper.properties
@@ -0,0 +1,5 @@
+distributionBase=GRADLE_USER_HOME
+distributionPath=wrapper/dists
+zipStoreBase=GRADLE_USER_HOME
+zipStorePath=wrapper/dists
+distributionUrl=https\://services.gradle.org/distributions/gradle-8.14-all.zip
--- a/android/settings.gradle.kts
+++ b/android/settings.gradle.kts
@@ -0,0 +1,26 @@
+pluginManagement {
+    val flutterSdkPath =
+        run {
+            val properties = java.util.Properties()
+            file("local.properties").inputStream().use { properties.load(it) }
+            val flutterSdkPath = properties.getProperty("flutter.sdk")
+            require(flutterSdkPath != null) { "flutter.sdk not set in local.properties" }
+            flutterSdkPath
+        }
+
+    includeBuild("$flutterSdkPath/packages/flutter_tools/gradle")
+
+    repositories {
+        google()
+        mavenCentral()
+        gradlePluginPortal()
+    }
+}
+
+plugins {
+    id("dev.flutter.flutter-plugin-loader") version "1.0.0"
+    id("com.android.application") version "8.11.1" apply false
+    id("org.jetbrains.kotlin.android") version "2.2.20" apply false
+}
+
+include(":app")
--- a/lib/camera_screen.dart
+++ b/lib/camera_screen.dart
@@ -0,0 +1,324 @@
+import 'dart:async';
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:camera/camera.dart';
+import 'package:flutter/material.dart';
+import 'package:permission_handler/permission_handler.dart';
+import 'package:wakelock_plus/wakelock_plus.dart';
+
+import 'package:external_cam/frame_server.dart';
+import 'package:external_cam/jpeg_encoder.dart';
+
+class CameraScreen extends StatefulWidget {
+  const CameraScreen({super.key});
+
+  @override
+  State<CameraScreen> createState() => _CameraScreenState();
+}
+
+class _CameraScreenState extends State<CameraScreen> {
+  CameraController? _controller;
+  final _server = FrameServer();
+  final _beacon = DiscoveryBeacon();
+  bool _isStreaming = false;
+  bool _isProcessing = false;
+  bool _flashOn = false;
+  String _error = '';
+  List<String> _addresses = [];
+  List<CameraDescription> _cameras = [];
+  int _cameraIndex = 0;
+  int _fps = 0;
+  int _frameCount = 0;
+  double _zoom = 1.0;
+  double _minZoom = 1.0;
+  double _maxZoom = 1.0;
+  int _quality = 50;
+  Timer? _fpsTimer;
+  StreamSubscription<String>? _commandSub;
+  StreamSubscription<void>? _connectSub;
+
+  @override
+  void initState() {
+    super.initState();
+    _init();
+  }
+
+  Future<void> _init() async {
+    try {
+      if (!await Permission.camera.request().isGranted) {
+        setState(() => _error = 'Camera permission required');
+        return;
+      }
+
+      _cameras = await availableCameras();
+      if (_cameras.isEmpty) {
+        setState(() => _error = 'No cameras found');
+        return;
+      }
+
+      await _initCamera(_cameras[_cameraIndex]);
+      await _startServer();
+    } catch (error) {
+      setState(() => _error = error.toString());
+    }
+  }
+
+  Future<void> _initCamera(CameraDescription camera) async {
+    await _controller?.dispose();
+    _flashOn = false;
+    _zoom = 1.0;
+    final controller = CameraController(
+      camera,
+      ResolutionPreset.high,
+      enableAudio: false,
+      imageFormatGroup: ImageFormatGroup.yuv420,
+    );
+    await controller.initialize();
+    if (!mounted) return;
+
+    _controller = controller;
+    _minZoom = await controller.getMinZoomLevel();
+    _maxZoom = await controller.getMaxZoomLevel();
+    setState(() {});
+  }
+
+  Future<void> _startServer() async {
+    await _server.start();
+    await _beacon.start();
+    _addresses = await _networkAddresses();
+
+    _commandSub = _server.commands.listen(_handleCommand);
+    _connectSub = _server.clientConnected.listen((_) => _broadcastState());
+
+    _fpsTimer = Timer.periodic(const Duration(seconds: 1), (_) {
+      if (!mounted) return;
+      setState(() {
+        _fps = _frameCount;
+        _frameCount = 0;
+      });
+    });
+
+    setState(() {});
+    _startStreaming();
+  }
+
+  void _handleCommand(String command) {
+    if (command.startsWith('zoom:')) {
+      final level = double.tryParse(command.substring(5));
+      if (level != null) _setZoom(level);
+      return;
+    }
+    if (command.startsWith('quality:')) {
+      final q = int.tryParse(command.substring(8));
+      if (q != null) _setQuality(q);
+      return;
+    }
+    switch (command) {
+      case 'switch_camera':
+        _switchCamera();
+      case 'toggle_flash':
+        _toggleFlash();
+    }
+  }
+
+  void _broadcastState() {
+    if (_cameras.isEmpty) return;
+    final camera = _cameras[_cameraIndex];
+    _server.sendText(
+      jsonEncode({
+        'cameras': _cameras.length,
+        'current': _cameraIndex,
+        'flash': _flashOn,
+        'lens': camera.lensDirection.name,
+        'name': camera.name,
+        'zoom': _zoom,
+        'minZoom': _minZoom,
+        'maxZoom': _maxZoom,
+        'quality': _quality,
+      }),
+    );
+  }
+
+  void _startStreaming() {
+    if (_isStreaming || _controller == null) return;
+    _controller!.startImageStream(_onFrame);
+    _isStreaming = true;
+    WakelockPlus.enable();
+  }
+
+  void _stopStreaming() {
+    if (!_isStreaming || _controller == null) return;
+    _controller!.stopImageStream();
+    _isStreaming = false;
+  }
+
+  void _onFrame(CameraImage image) {
+    if (_isProcessing || _server.clientCount == 0) return;
+    _isProcessing = true;
+
+    encodeJpeg(image, quality: _quality).then((jpeg) {
+      if (jpeg != null) {
+        _server.sendFrame(jpeg);
+        _frameCount++;
+      }
+    }).whenComplete(() {
+      _isProcessing = false;
+    });
+  }
+
+  Future<List<String>> _networkAddresses() async {
+    final interfaces = await NetworkInterface.list();
+    final results = <String>[];
+    for (final iface in interfaces) {
+      for (final addr in iface.addresses) {
+        if (addr.type != InternetAddressType.IPv4 || addr.isLoopback) continue;
+        results.add('${addr.address} (${iface.name})');
+      }
+    }
+    return results;
+  }
+
+  Future<void> _switchCamera() async {
+    if (_cameras.length < 2) return;
+    _stopStreaming();
+    _cameraIndex = (_cameraIndex + 1) % _cameras.length;
+    await _initCamera(_cameras[_cameraIndex]);
+    _startStreaming();
+    _broadcastState();
+  }
+
+  Future<void> _setZoom(double level) async {
+    final controller = _controller;
+    if (controller == null) return;
+
+    _zoom = level.clamp(_minZoom, _maxZoom);
+    await controller.setZoomLevel(_zoom);
+    setState(() {});
+    _broadcastState();
+  }
+
+  void _setQuality(int value) {
+    _quality = value.clamp(10, 100);
+    setState(() {});
+    _broadcastState();
+  }
+
+  Future<void> _toggleFlash() async {
+    final controller = _controller;
+    if (controller == null) return;
+
+    try {
+      _stopStreaming();
+      _flashOn = !_flashOn;
+      await controller.setFlashMode(
+        _flashOn ? FlashMode.torch : FlashMode.off,
+      );
+    } catch (_) {
+      _flashOn = false;
+    } finally {
+      _startStreaming();
+      setState(() {});
+      _broadcastState();
+    }
+  }
+
+  @override
+  void dispose() {
+    _fpsTimer?.cancel();
+    _commandSub?.cancel();
+    _connectSub?.cancel();
+    _stopStreaming();
+    _controller?.dispose();
+    _beacon.stop();
+    _server.stop();
+    WakelockPlus.disable();
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    if (_error.isNotEmpty) {
+      return Scaffold(
+        appBar: AppBar(title: const Text('Camera')),
+        body: Center(
+          child: Padding(
+            padding: const EdgeInsets.all(32),
+            child: Text(_error, textAlign: TextAlign.center),
+          ),
+        ),
+      );
+    }
+
+    return Scaffold(
+      backgroundColor: Colors.black,
+      body: Stack(
+        fit: StackFit.expand,
+        children: [
+          if (_controller?.value.isInitialized ?? false)
+            Center(child: CameraPreview(_controller!)),
+          SafeArea(
+            child: Column(
+              children: [_buildInfoBar(), const Spacer(), _buildControls()],
+            ),
+          ),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildInfoBar() {
+    final addressText =
+        _addresses.isNotEmpty ? _addresses.join('\n') : 'No network';
+
+    return Container(
+      margin: const EdgeInsets.all(16),
+      padding: const EdgeInsets.symmetric(horizontal: 16, vertical: 10),
+      decoration: BoxDecoration(
+        color: Colors.black54,
+        borderRadius: BorderRadius.circular(8),
+      ),
+      child: Row(
+        children: [
+          Icon(
+            Icons.circle,
+            color: _server.clientCount > 0 ? Colors.green : Colors.red,
+            size: 12,
+          ),
+          const SizedBox(width: 10),
+          Expanded(
+            child: Text(addressText, style: const TextStyle(fontSize: 13)),
+          ),
+          Text('${_server.clientCount} viewers  $_fps fps'),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildControls() {
+    return Padding(
+      padding: const EdgeInsets.all(24),
+      child: Row(
+        mainAxisAlignment: MainAxisAlignment.spaceEvenly,
+        children: [
+          IconButton.filled(
+            onPressed: () => Navigator.pop(context),
+            icon: const Icon(Icons.arrow_back),
+            iconSize: 28,
+          ),
+          if (_cameras.length > 1)
+            IconButton.filled(
+              onPressed: _switchCamera,
+              icon: const Icon(Icons.flip_camera_android),
+              iconSize: 28,
+            ),
+          IconButton.filled(
+            onPressed: _toggleFlash,
+            icon: Icon(_flashOn ? Icons.flash_on : Icons.flash_off),
+            iconSize: 28,
+          ),
+        ],
+      ),
+    );
+  }
+}
--- a/lib/frame_server.dart
+++ b/lib/frame_server.dart
@@ -0,0 +1,182 @@
+import 'dart:async';
+import 'dart:convert';
+import 'dart:io';
+import 'dart:typed_data';
+
+const serverPort = 8080;
+const discoveryPort = 8081;
+const _beacon = 'EXTCAM';
+
+class FrameServer {
+  HttpServer? _httpServer;
+  final List<WebSocket> _clients = [];
+  final _commands = StreamController<String>.broadcast();
+  final _connections = StreamController<void>.broadcast();
+
+  int get clientCount => _clients.length;
+  Stream<String> get commands => _commands.stream;
+  Stream<void> get clientConnected => _connections.stream;
+
+  Future<void> start() async {
+    _httpServer = await HttpServer.bind(InternetAddress.anyIPv4, serverPort);
+    _httpServer!.listen(_handleRequest);
+  }
+
+  void _handleRequest(HttpRequest request) {
+    if (request.uri.path == '/stream') {
+      _upgradeToWebSocket(request);
+    } else {
+      request.response
+        ..statusCode = HttpStatus.ok
+        ..headers.contentType = ContentType.json
+        ..write('{"clients":${_clients.length}}')
+        ..close();
+    }
+  }
+
+  Future<void> _upgradeToWebSocket(HttpRequest request) async {
+    final socket = await WebSocketTransformer.upgrade(request);
+    _clients.add(socket);
+    _connections.add(null);
+    socket.listen((data) {
+      if (data is String) _commands.add(data);
+    }, onDone: () => _clients.remove(socket));
+  }
+
+  void sendFrame(Uint8List jpeg) {
+    for (final client in _clients.toList()) {
+      try {
+        client.add(jpeg);
+      } catch (_) {
+        _clients.remove(client);
+      }
+    }
+  }
+
+  void sendText(String message) {
+    for (final client in _clients.toList()) {
+      try {
+        client.add(message);
+      } catch (_) {
+        _clients.remove(client);
+      }
+    }
+  }
+
+  Future<void> stop() async {
+    await _commands.close();
+    await _connections.close();
+    for (final client in _clients.toList()) {
+      await client.close();
+    }
+    _clients.clear();
+    await _httpServer?.close();
+    _httpServer = null;
+  }
+}
+
+class DiscoveryBeacon {
+  RawDatagramSocket? _socket;
+  Timer? _timer;
+
+  Future<void> start() async {
+    _socket = await RawDatagramSocket.bind(InternetAddress.anyIPv4, 0);
+    _socket!.broadcastEnabled = true;
+    _sendBroadcast();
+    _timer = Timer.periodic(
+      const Duration(seconds: 1),
+      (_) => _sendBroadcast(),
+    );
+  }
+
+  Future<void> _sendBroadcast() async {
+    final data = utf8.encode(_beacon);
+    final socket = _socket;
+    if (socket == null) return;
+
+    // global broadcast
+    socket.send(data, InternetAddress('255.255.255.255'), discoveryPort);
+
+    // subnet-specific broadcasts (needed on hotspot/tethering)
+    final interfaces = await NetworkInterface.list();
+    for (final iface in interfaces) {
+      for (final addr in iface.addresses) {
+        if (addr.type != InternetAddressType.IPv4 || addr.isLoopback) continue;
+        final parts = addr.address.split('.');
+        final subnetBroadcast = '${parts[0]}.${parts[1]}.${parts[2]}.255';
+        socket.send(data, InternetAddress(subnetBroadcast), discoveryPort);
+      }
+    }
+  }
+
+  void stop() {
+    _timer?.cancel();
+    _socket?.close();
+  }
+}
+
+Future<String?> discoverServer({
+  Duration timeout = const Duration(seconds: 5),
+}) async {
+  final results = await Future.wait([
+    _discoverViaBroadcast(timeout),
+    _discoverViaProbe(),
+  ]);
+  return results.firstWhere((r) => r != null, orElse: () => null);
+}
+
+Future<String?> _discoverViaBroadcast(Duration timeout) async {
+  final socket = await RawDatagramSocket.bind(
+    InternetAddress.anyIPv4,
+    discoveryPort,
+  );
+  try {
+    await for (final event in socket.timeout(timeout)) {
+      if (event == RawSocketEvent.read) {
+        final datagram = socket.receive();
+        if (datagram == null) continue;
+        final message = utf8.decode(datagram.data);
+        if (message == _beacon) return datagram.address.address;
+      }
+    }
+  } on TimeoutException {
+    // no server found
+  } finally {
+    socket.close();
+  }
+  return null;
+}
+
+Future<String?> _discoverViaProbe() async {
+  final interfaces = await NetworkInterface.list();
+  final candidates = <String>{};
+
+  for (final iface in interfaces) {
+    for (final addr in iface.addresses) {
+      if (addr.type != InternetAddressType.IPv4 || addr.isLoopback) continue;
+      final parts = addr.address.split('.');
+      final subnet = '${parts[0]}.${parts[1]}.${parts[2]}';
+      for (var suffix = 1; suffix <= 254; suffix++) {
+        final candidate = '$subnet.$suffix';
+        if (candidate != addr.address) candidates.add(candidate);
+      }
+    }
+  }
+
+  final futures = candidates.map((ip) async {
+    try {
+      final socket = await Socket.connect(
+        ip,
+        serverPort,
+        timeout: const Duration(milliseconds: 800),
+      );
+      socket.destroy();
+      return ip;
+    } catch (_) {
+      return null;
+    }
+  });
+
+  final results = await Future.wait(futures);
+  return results.whereType<String>().firstOrNull;
+}
--- a/lib/home_screen.dart
+++ b/lib/home_screen.dart
@@ -0,0 +1,97 @@
+import 'package:flutter/material.dart';
+
+import 'package:external_cam/camera_screen.dart';
+import 'package:external_cam/viewer_screen.dart';
+
+class HomeScreen extends StatelessWidget {
+  const HomeScreen({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return Scaffold(
+      appBar: AppBar(title: const Text('External Cam')),
+      body: Center(
+        child: Padding(
+          padding: const EdgeInsets.all(32),
+          child: Column(
+            mainAxisAlignment: MainAxisAlignment.center,
+            children: [
+              _ModeCard(
+                icon: Icons.camera_alt,
+                title: 'Camera',
+                subtitle: 'Stream this device\'s camera over USB',
+                onTap: () => Navigator.push(
+                  context,
+                  MaterialPageRoute(builder: (_) => const CameraScreen()),
+                ),
+              ),
+              const SizedBox(height: 24),
+              _ModeCard(
+                icon: Icons.tv,
+                title: 'Viewer',
+                subtitle: 'View the camera stream from a connected device',
+                onTap: () => Navigator.push(
+                  context,
+                  MaterialPageRoute(builder: (_) => const ViewerScreen()),
+                ),
+              ),
+              const SizedBox(height: 32),
+              Text(
+                'Connect both devices with USB-C, then enable\n'
+                'USB tethering on the camera device.',
+                textAlign: TextAlign.center,
+                style: Theme.of(context).textTheme.bodySmall,
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}
+
+class _ModeCard extends StatelessWidget {
+  const _ModeCard({
+    required this.icon,
+    required this.title,
+    required this.subtitle,
+    required this.onTap,
+  });
+
+  final IconData icon;
+  final String title;
+  final String subtitle;
+  final VoidCallback onTap;
+
+  @override
+  Widget build(BuildContext context) {
+    return Card(
+      child: InkWell(
+        onTap: onTap,
+        borderRadius: BorderRadius.circular(12),
+        child: Padding(
+          padding: const EdgeInsets.all(32),
+          child: Row(
+            children: [
+              Icon(icon, size: 48),
+              const SizedBox(width: 24),
+              Expanded(
+                child: Column(
+                  crossAxisAlignment: CrossAxisAlignment.start,
+                  children: [
+                    Text(
+                      title,
+                      style: Theme.of(context).textTheme.headlineSmall,
+                    ),
+                    Text(subtitle),
+                  ],
+                ),
+              ),
+              const Icon(Icons.chevron_right),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+}
--- a/lib/jpeg_encoder.dart
+++ b/lib/jpeg_encoder.dart
@@ -0,0 +1,18 @@
+import 'package:camera/camera.dart';
+import 'package:flutter/services.dart';
+
+const _channel = MethodChannel('com.kschappell.external_cam/jpeg');
+
+Future<Uint8List?> encodeJpeg(CameraImage image, {int quality = 50}) async {
+  return _channel.invokeMethod<Uint8List>('encodeJpeg', {
+    'width': image.width,
+    'height': image.height,
+    'y': image.planes[0].bytes,
+    'u': image.planes[1].bytes,
+    'v': image.planes[2].bytes,
+    'yRowStride': image.planes[0].bytesPerRow,
+    'uvRowStride': image.planes[1].bytesPerRow,
+    'uvPixelStride': image.planes[1].bytesPerPixel,
+    'quality': quality,
+  });
+}
--- a/lib/main.dart
+++ b/lib/main.dart
@@ -0,0 +1,25 @@
+import 'package:flutter/material.dart';
+
+import 'package:external_cam/home_screen.dart';
+
+void main() {
+  runApp(const ExternalCamApp());
+}
+
+class ExternalCamApp extends StatelessWidget {
+  const ExternalCamApp({super.key});
+
+  @override
+  Widget build(BuildContext context) {
+    return MaterialApp(
+      title: 'External Cam',
+      theme: ThemeData.dark(useMaterial3: true).copyWith(
+        colorScheme: ColorScheme.fromSeed(
+          seedColor: Colors.teal,
+          brightness: Brightness.dark,
+        ),
+      ),
+      home: const HomeScreen(),
+    );
+  }
+}
--- a/lib/viewer_screen.dart
+++ b/lib/viewer_screen.dart
@@ -0,0 +1,390 @@
+import 'dart:async';
+import 'dart:convert';
+import 'dart:io';
+
+import 'package:flutter/material.dart';
+import 'package:flutter/services.dart';
+import 'package:wakelock_plus/wakelock_plus.dart';
+
+import 'package:external_cam/frame_server.dart';
+
+class ViewerScreen extends StatefulWidget {
+  const ViewerScreen({super.key});
+
+  @override
+  State<ViewerScreen> createState() => _ViewerScreenState();
+}
+
+class _ViewerScreenState extends State<ViewerScreen> {
+  final _ipController = TextEditingController();
+  WebSocket? _socket;
+  Uint8List? _currentFrame;
+  bool _isConnected = false;
+  bool _isSearching = true;
+  bool _isConnecting = false;
+  int _fps = 0;
+  int _frameCount = 0;
+  int _rotation = 0;
+  bool _mirrored = false;
+  Timer? _fpsTimer;
+
+  int _cameraCount = 0;
+  bool _flashOn = false;
+  String _lensDirection = '';
+  String _cameraName = '';
+  double _zoom = 1.0;
+  double _minZoom = 1.0;
+  double _maxZoom = 1.0;
+  int _quality = 50;
+
+  @override
+  void initState() {
+    super.initState();
+    SystemChrome.setPreferredOrientations([
+      DeviceOrientation.landscapeLeft,
+      DeviceOrientation.landscapeRight,
+    ]);
+    SystemChrome.setEnabledSystemUIMode(SystemUiMode.immersiveSticky);
+    _autoDiscover();
+  }
+
+  Future<void> _autoDiscover() async {
+    setState(() => _isSearching = true);
+    final ip = await discoverServer();
+    if (!mounted) return;
+
+    if (ip != null) {
+      _ipController.text = ip;
+      _connectTo(ip);
+    } else {
+      setState(() => _isSearching = false);
+    }
+  }
+
+  Future<void> _connectTo(String ip) async {
+    if (_isConnecting) return;
+    setState(() {
+      _isConnecting = true;
+      _isSearching = false;
+    });
+
+    try {
+      _socket = await WebSocket.connect(
+        'ws://$ip:$serverPort/stream',
+      ).timeout(const Duration(seconds: 5));
+
+      _fpsTimer = Timer.periodic(const Duration(seconds: 1), (_) {
+        if (!mounted) return;
+        setState(() {
+          _fps = _frameCount;
+          _frameCount = 0;
+        });
+      });
+
+      _socket!.listen(
+        _onData,
+        onDone: _onDisconnected,
+        onError: (_) => _onDisconnected(),
+      );
+
+      setState(() {
+        _isConnected = true;
+        _isConnecting = false;
+      });
+      WakelockPlus.enable();
+    } catch (error) {
+      setState(() => _isConnecting = false);
+      if (mounted) {
+        ScaffoldMessenger.of(
+          context,
+        ).showSnackBar(SnackBar(content: Text('Connection failed: $error')));
+      }
+    }
+  }
+
+  void _connect() {
+    final ip = _ipController.text.trim();
+    if (ip.isNotEmpty) _connectTo(ip);
+  }
+
+  void _onData(dynamic data) {
+    if (data is List<int>) {
+      setState(() {
+        _currentFrame = Uint8List.fromList(data);
+        _frameCount++;
+      });
+    } else if (data is String) {
+      _handleState(data);
+    }
+  }
+
+  void _handleState(String json) {
+    try {
+      final state = jsonDecode(json) as Map<String, dynamic>;
+      setState(() {
+        _cameraCount = state['cameras'] as int? ?? 0;
+        _flashOn = state['flash'] as bool? ?? false;
+        _lensDirection = state['lens'] as String? ?? '';
+        _cameraName = state['name'] as String? ?? '';
+        _zoom = (state['zoom'] as num?)?.toDouble() ?? 1.0;
+        _minZoom = (state['minZoom'] as num?)?.toDouble() ?? 1.0;
+        _maxZoom = (state['maxZoom'] as num?)?.toDouble() ?? 1.0;
+        _quality = state['quality'] as int? ?? 50;
+      });
+    } catch (_) {}
+  }
+
+  void _sendCommand(String command) => _socket?.add(command);
+
+  void _onDisconnected() {
+    _fpsTimer?.cancel();
+    _fpsTimer = null;
+    if (!mounted) return;
+    setState(() {
+      _isConnected = false;
+      _currentFrame = null;
+    });
+    WakelockPlus.disable();
+  }
+
+  void _disconnect() {
+    _socket?.close();
+    _onDisconnected();
+  }
+
+  void _cycleRotation() {
+    setState(() => _rotation = (_rotation + 1) % 4);
+  }
+
+  @override
+  void dispose() {
+    _fpsTimer?.cancel();
+    _socket?.close();
+    _ipController.dispose();
+    WakelockPlus.disable();
+    SystemChrome.setPreferredOrientations(DeviceOrientation.values);
+    SystemChrome.setEnabledSystemUIMode(SystemUiMode.edgeToEdge);
+    super.dispose();
+  }
+
+  @override
+  Widget build(BuildContext context) {
+    if (_isConnected) return _buildViewer();
+    return _buildConnectScreen();
+  }
+
+  Widget _buildConnectScreen() {
+    return Scaffold(
+      appBar: AppBar(title: const Text('Viewer')),
+      body: Center(
+        child: Padding(
+          padding: const EdgeInsets.all(32),
+          child: Column(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              if (_isSearching) ...[
+                const CircularProgressIndicator(),
+                const SizedBox(height: 16),
+                const Text('Searching for camera...'),
+              ] else ...[
+                TextField(
+                  controller: _ipController,
+                  decoration: const InputDecoration(
+                    labelText: 'Camera IP address',
+                    border: OutlineInputBorder(),
+                  ),
+                  keyboardType: TextInputType.number,
+                  onSubmitted: (_) => _connect(),
+                ),
+                const SizedBox(height: 16),
+                Row(
+                  mainAxisAlignment: MainAxisAlignment.center,
+                  children: [
+                    FilledButton.icon(
+                      onPressed: _isConnecting ? null : _connect,
+                      icon: _isConnecting
+                          ? const SizedBox(
+                              width: 16,
+                              height: 16,
+                              child: CircularProgressIndicator(strokeWidth: 2),
+                            )
+                          : const Icon(Icons.play_arrow),
+                      label: Text(_isConnecting ? 'Connecting...' : 'Connect'),
+                    ),
+                    const SizedBox(width: 16),
+                    OutlinedButton.icon(
+                      onPressed: _isConnecting ? null : _autoDiscover,
+                      icon: const Icon(Icons.search),
+                      label: const Text('Search'),
+                    ),
+                  ],
+                ),
+              ],
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  Widget _buildViewer() {
+    return Scaffold(
+      backgroundColor: Colors.black,
+      body: Stack(
+        fit: StackFit.expand,
+        children: [
+          if (_currentFrame != null)
+            Center(
+              child: Transform.flip(
+                flipX: _mirrored,
+                child: RotatedBox(
+                  quarterTurns: _rotation,
+                  child: Image.memory(
+                    _currentFrame!,
+                    gaplessPlayback: true,
+                    fit: BoxFit.contain,
+                  ),
+                ),
+              ),
+            ),
+          _buildTopBar(),
+          _buildBottomControls(),
+        ],
+      ),
+    );
+  }
+
+  Widget _buildTopBar() {
+    return Positioned(
+      top: 16,
+      right: 16,
+      child: SafeArea(
+        child: Container(
+          padding: const EdgeInsets.symmetric(horizontal: 12, vertical: 6),
+          decoration: BoxDecoration(
+            color: Colors.black54,
+            borderRadius: BorderRadius.circular(8),
+          ),
+          child: Row(
+            mainAxisSize: MainAxisSize.min,
+            children: [
+              const Icon(Icons.circle, color: Colors.green, size: 12),
+              const SizedBox(width: 8),
+              Text('$_fps fps'),
+              if (_cameraName.isNotEmpty) ...[
+                const SizedBox(width: 8),
+                Text(
+                  '$_lensDirection $_cameraName',
+                  style: const TextStyle(fontSize: 12),
+                ),
+              ],
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  List<double> get _availableZoomPresets {
+    const presets = [0.5, 1.0, 2.0, 3.0, 5.0, 10.0];
+    return presets.where((z) => z >= _minZoom && z <= _maxZoom).toList();
+  }
+
+  Widget _buildBottomControls() {
+    return Positioned(
+      bottom: 0,
+      left: 0,
+      right: 0,
+      child: SafeArea(
+        child: Container(
+          padding: const EdgeInsets.symmetric(vertical: 8, horizontal: 8),
+          decoration: const BoxDecoration(
+            gradient: LinearGradient(
+              begin: Alignment.bottomCenter,
+              end: Alignment.topCenter,
+              colors: [Colors.black54, Colors.transparent],
+            ),
+          ),
+          child: Row(
+            children: [
+              IconButton(
+                onPressed: _disconnect,
+                icon: const Icon(Icons.close, size: 20),
+                visualDensity: VisualDensity.compact,
+              ),
+              if (_cameraCount > 1)
+                IconButton(
+                  onPressed: () => _sendCommand('switch_camera'),
+                  icon: const Icon(Icons.flip_camera_android, size: 20),
+                  visualDensity: VisualDensity.compact,
+                ),
+              IconButton(
+                onPressed: () => _sendCommand('toggle_flash'),
+                icon: Icon(
+                  _flashOn ? Icons.flash_on : Icons.flash_off,
+                  size: 20,
+                ),
+                visualDensity: VisualDensity.compact,
+              ),
+              IconButton(
+                onPressed: _cycleRotation,
+                icon: const Icon(Icons.rotate_right, size: 20),
+                visualDensity: VisualDensity.compact,
+              ),
+              IconButton(
+                onPressed: () => setState(() => _mirrored = !_mirrored),
+                icon: const Icon(Icons.flip, size: 20),
+                visualDensity: VisualDensity.compact,
+              ),
+              const Spacer(),
+              if (_availableZoomPresets.length > 1)
+                ..._buildChipGroup(
+                  _availableZoomPresets.map((level) {
+                    final active = (_zoom - level).abs() < 0.1;
+                    final label = level == level.roundToDouble()
+                        ? '${level.toInt()}x'
+                        : '${level}x';
+                    return _chip(label, active, () => _sendCommand('zoom:$level'));
+                  }),
+                ),
+              const SizedBox(width: 8),
+              ..._buildChipGroup(
+                [30, 50, 70, 90].map(
+                  (q) => _chip('$q%', _quality == q, () => _sendCommand('quality:$q')),
+                ),
+              ),
+            ],
+          ),
+        ),
+      ),
+    );
+  }
+
+  List<Widget> _buildChipGroup(Iterable<Widget> chips) => chips.toList();
+
+  Widget _chip(String label, bool active, VoidCallback onTap) {
+    return Padding(
+      padding: const EdgeInsets.symmetric(horizontal: 2),
+      child: GestureDetector(
+        onTap: onTap,
+        child: Container(
+          padding: const EdgeInsets.symmetric(horizontal: 8, vertical: 4),
+          decoration: BoxDecoration(
+            color: active ? Colors.white24 : Colors.transparent,
+            borderRadius: BorderRadius.circular(12),
+            border: Border.all(
+              color: active ? Colors.white70 : Colors.white30,
+            ),
+          ),
+          child: Text(
+            label,
+            style: TextStyle(
+              fontSize: 11,
+              color: active ? Colors.white : Colors.white70,
+            ),
+          ),
+        ),
+      ),
+    );
+  }
+}
--- a/pubspec.lock
+++ b/pubspec.lock
@@ -0,0 +1,442 @@
+# Generated by pub
+# See https://dart.dev/tools/pub/glossary#lockfile
+packages:
+  args:
+    dependency: transitive
+    description:
+      name: args
+      sha256: d0481093c50b1da8910eb0bb301626d4d8eb7284aa739614d2b394ee09e3ea04
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.7.0"
+  async:
+    dependency: transitive
+    description:
+      name: async
+      sha256: "758e6d74e971c3e5aceb4110bfd6698efc7f501675bcfe0c775459a8140750eb"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.13.0"
+  boolean_selector:
+    dependency: transitive
+    description:
+      name: boolean_selector
+      sha256: "8aab1771e1243a5063b8b0ff68042d67334e3feab9e95b9490f9a6ebf73b42ea"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.2"
+  camera:
+    dependency: "direct main"
+    description:
+      name: camera
+      sha256: "4142a19a38e388d3bab444227636610ba88982e36dff4552d5191a86f65dc437"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.11.4"
+  camera_android_camerax:
+    dependency: transitive
+    description:
+      name: camera_android_camerax
+      sha256: "8516fe308bc341a5067fb1a48edff0ddfa57c0d3cdcc9dbe7ceca3ba119e2577"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.6.30"
+  camera_avfoundation:
+    dependency: transitive
+    description:
+      name: camera_avfoundation
+      sha256: "11b4aee2f5e5e038982e152b4a342c749b414aa27857899d20f4323e94cb5f0b"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.9.23+2"
+  camera_platform_interface:
+    dependency: transitive
+    description:
+      name: camera_platform_interface
+      sha256: "98cfc9357e04bad617671b4c1f78a597f25f08003089dd94050709ae54effc63"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.12.0"
+  camera_web:
+    dependency: transitive
+    description:
+      name: camera_web
+      sha256: "57f49a635c8bf249d07fb95eb693d7e4dda6796dedb3777f9127fb54847beba7"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.3.5+3"
+  characters:
+    dependency: transitive
+    description:
+      name: characters
+      sha256: faf38497bda5ead2a8c7615f4f7939df04333478bf32e4173fcb06d428b5716b
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.4.1"
+  clock:
+    dependency: transitive
+    description:
+      name: clock
+      sha256: fddb70d9b5277016c77a80201021d40a2247104d9f4aa7bab7157b7e3f05b84b
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.2"
+  collection:
+    dependency: transitive
+    description:
+      name: collection
+      sha256: "2f5709ae4d3d59dd8f7cd309b4e023046b57d8a6c82130785d2b0e5868084e76"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.19.1"
+  cross_file:
+    dependency: transitive
+    description:
+      name: cross_file
+      sha256: "28bb3ae56f117b5aec029d702a90f57d285cd975c3c5c281eaca38dbc47c5937"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.3.5+2"
+  dbus:
+    dependency: transitive
+    description:
+      name: dbus
+      sha256: d0c98dcd4f5169878b6cf8f6e0a52403a9dff371a3e2f019697accbf6f44a270
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.7.12"
+  fake_async:
+    dependency: transitive
+    description:
+      name: fake_async
+      sha256: "5368f224a74523e8d2e7399ea1638b37aecfca824a3cc4dfdf77bf1fa905ac44"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.3.3"
+  ffi:
+    dependency: transitive
+    description:
+      name: ffi
+      sha256: "6d7fd89431262d8f3125e81b50d3847a091d846eafcd4fdb88dd06f36d705a45"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.0"
+  flutter:
+    dependency: "direct main"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  flutter_lints:
+    dependency: "direct dev"
+    description:
+      name: flutter_lints
+      sha256: "3105dc8492f6183fb076ccf1f351ac3d60564bff92e20bfc4af9cc1651f4e7e1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.0.0"
+  flutter_plugin_android_lifecycle:
+    dependency: transitive
+    description:
+      name: flutter_plugin_android_lifecycle
+      sha256: ee8068e0e1cd16c4a82714119918efdeed33b3ba7772c54b5d094ab53f9b7fd1
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.0.33"
+  flutter_test:
+    dependency: "direct dev"
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  flutter_web_plugins:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  http:
+    dependency: transitive
+    description:
+      name: http
+      sha256: "87721a4a50b19c7f1d49001e51409bddc46303966ce89a65af4f4e6004896412"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.6.0"
+  http_parser:
+    dependency: transitive
+    description:
+      name: http_parser
+      sha256: "178d74305e7866013777bab2c3d8726205dc5a4dd935297175b19a23a2e66571"
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.1.2"
+  leak_tracker:
+    dependency: transitive
+    description:
+      name: leak_tracker
+      sha256: "33e2e26bdd85a0112ec15400c8cbffea70d0f9c3407491f672a2fad47915e2de"
+      url: "https://pub.dev"
+    source: hosted
+    version: "11.0.2"
+  leak_tracker_flutter_testing:
+    dependency: transitive
+    description:
+      name: leak_tracker_flutter_testing
+      sha256: "1dbc140bb5a23c75ea9c4811222756104fbcd1a27173f0c34ca01e16bea473c1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.10"
+  leak_tracker_testing:
+    dependency: transitive
+    description:
+      name: leak_tracker_testing
+      sha256: "8d5a2d49f4a66b49744b23b018848400d23e54caf9463f4eb20df3eb8acb2eb1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.0.2"
+  lints:
+    dependency: transitive
+    description:
+      name: lints
+      sha256: "12f842a479589fea194fe5c5a3095abc7be0c1f2ddfa9a0e76aed1dbd26a87df"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.1.0"
+  matcher:
+    dependency: transitive
+    description:
+      name: matcher
+      sha256: "12956d0ad8390bbcc63ca2e1469c0619946ccb52809807067a7020d57e647aa6"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.12.18"
+  material_color_utilities:
+    dependency: transitive
+    description:
+      name: material_color_utilities
+      sha256: "9c337007e82b1889149c82ed242ed1cb24a66044e30979c44912381e9be4c48b"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.13.0"
+  meta:
+    dependency: transitive
+    description:
+      name: meta
+      sha256: "23f08335362185a5ea2ad3a4e597f1375e78bce8a040df5c600c8d3552ef2394"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.17.0"
+  package_info_plus:
+    dependency: transitive
+    description:
+      name: package_info_plus
+      sha256: f69da0d3189a4b4ceaeb1a3defb0f329b3b352517f52bed4290f83d4f06bc08d
+      url: "https://pub.dev"
+    source: hosted
+    version: "9.0.0"
+  package_info_plus_platform_interface:
+    dependency: transitive
+    description:
+      name: package_info_plus_platform_interface
+      sha256: "202a487f08836a592a6bd4f901ac69b3a8f146af552bbd14407b6b41e1c3f086"
+      url: "https://pub.dev"
+    source: hosted
+    version: "3.2.1"
+  path:
+    dependency: transitive
+    description:
+      name: path
+      sha256: "75cca69d1490965be98c73ceaea117e8a04dd21217b37b292c9ddbec0d955bc5"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.9.1"
+  permission_handler:
+    dependency: "direct main"
+    description:
+      name: permission_handler
+      sha256: "59adad729136f01ea9e35a48f5d1395e25cba6cea552249ddbe9cf950f5d7849"
+      url: "https://pub.dev"
+    source: hosted
+    version: "11.4.0"
+  permission_handler_android:
+    dependency: transitive
+    description:
+      name: permission_handler_android
+      sha256: d3971dcdd76182a0c198c096b5db2f0884b0d4196723d21a866fc4cdea057ebc
+      url: "https://pub.dev"
+    source: hosted
+    version: "12.1.0"
+  permission_handler_apple:
+    dependency: transitive
+    description:
+      name: permission_handler_apple
+      sha256: f000131e755c54cf4d84a5d8bd6e4149e262cc31c5a8b1d698de1ac85fa41023
+      url: "https://pub.dev"
+    source: hosted
+    version: "9.4.7"
+  permission_handler_html:
+    dependency: transitive
+    description:
+      name: permission_handler_html
+      sha256: "38f000e83355abb3392140f6bc3030660cfaef189e1f87824facb76300b4ff24"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.1.3+5"
+  permission_handler_platform_interface:
+    dependency: transitive
+    description:
+      name: permission_handler_platform_interface
+      sha256: eb99b295153abce5d683cac8c02e22faab63e50679b937fa1bf67d58bb282878
+      url: "https://pub.dev"
+    source: hosted
+    version: "4.3.0"
+  permission_handler_windows:
+    dependency: transitive
+    description:
+      name: permission_handler_windows
+      sha256: "1a790728016f79a41216d88672dbc5df30e686e811ad4e698bfc51f76ad91f1e"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.2.1"
+  petitparser:
+    dependency: transitive
+    description:
+      name: petitparser
+      sha256: "91bd59303e9f769f108f8df05e371341b15d59e995e6806aefab827b58336675"
+      url: "https://pub.dev"
+    source: hosted
+    version: "7.0.2"
+  plugin_platform_interface:
+    dependency: transitive
+    description:
+      name: plugin_platform_interface
+      sha256: "4820fbfdb9478b1ebae27888254d445073732dae3d6ea81f0b7e06d5dedc3f02"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.8"
+  sky_engine:
+    dependency: transitive
+    description: flutter
+    source: sdk
+    version: "0.0.0"
+  source_span:
+    dependency: transitive
+    description:
+      name: source_span
+      sha256: "56a02f1f4cd1a2d96303c0144c93bd6d909eea6bee6bf5a0e0b685edbd4c47ab"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.10.2"
+  stack_trace:
+    dependency: transitive
+    description:
+      name: stack_trace
+      sha256: "8b27215b45d22309b5cddda1aa2b19bdfec9df0e765f2de506401c071d38d1b1"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.12.1"
+  stream_channel:
+    dependency: transitive
+    description:
+      name: stream_channel
+      sha256: "969e04c80b8bcdf826f8f16579c7b14d780458bd97f56d107d3950fdbeef059d"
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.4"
+  stream_transform:
+    dependency: transitive
+    description:
+      name: stream_transform
+      sha256: ad47125e588cfd37a9a7f86c7d6356dde8dfe89d071d293f80ca9e9273a33871
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.1.1"
+  string_scanner:
+    dependency: transitive
+    description:
+      name: string_scanner
+      sha256: "921cd31725b72fe181906c6a94d987c78e3b98c2e205b397ea399d4054872b43"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.4.1"
+  term_glyph:
+    dependency: transitive
+    description:
+      name: term_glyph
+      sha256: "7f554798625ea768a7518313e58f83891c7f5024f88e46e7182a4558850a4b8e"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.2.2"
+  test_api:
+    dependency: transitive
+    description:
+      name: test_api
+      sha256: "19a78f63e83d3a61f00826d09bc2f60e191bf3504183c001262be6ac75589fb8"
+      url: "https://pub.dev"
+    source: hosted
+    version: "0.7.8"
+  typed_data:
+    dependency: transitive
+    description:
+      name: typed_data
+      sha256: f9049c039ebfeb4cf7a7104a675823cd72dba8297f264b6637062516699fa006
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.4.0"
+  vector_math:
+    dependency: transitive
+    description:
+      name: vector_math
+      sha256: d530bd74fea330e6e364cda7a85019c434070188383e1cd8d9777ee586914c5b
+      url: "https://pub.dev"
+    source: hosted
+    version: "2.2.0"
+  vm_service:
+    dependency: transitive
+    description:
+      name: vm_service
+      sha256: "45caa6c5917fa127b5dbcfbd1fa60b14e583afdc08bfc96dda38886ca252eb60"
+      url: "https://pub.dev"
+    source: hosted
+    version: "15.0.2"
+  wakelock_plus:
+    dependency: "direct main"
+    description:
+      name: wakelock_plus
+      sha256: "9296d40c9adbedaba95d1e704f4e0b434be446e2792948d0e4aa977048104228"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.4.0"
+  wakelock_plus_platform_interface:
+    dependency: transitive
+    description:
+      name: wakelock_plus_platform_interface
+      sha256: "036deb14cd62f558ca3b73006d52ce049fabcdcb2eddfe0bf0fe4e8a943b5cf2"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.3.0"
+  web:
+    dependency: transitive
+    description:
+      name: web
+      sha256: "868d88a33d8a87b18ffc05f9f030ba328ffefba92d6c127917a2ba740f9cfe4a"
+      url: "https://pub.dev"
+    source: hosted
+    version: "1.1.1"
+  win32:
+    dependency: transitive
+    description:
+      name: win32
+      sha256: d7cb55e04cd34096cd3a79b3330245f54cb96a370a1c27adb3c84b917de8b08e
+      url: "https://pub.dev"
+    source: hosted
+    version: "5.15.0"
+  xml:
+    dependency: transitive
+    description:
+      name: xml
+      sha256: "971043b3a0d3da28727e40ed3e0b5d18b742fa5a68665cca88e74b7876d5e025"
+      url: "https://pub.dev"
+    source: hosted
+    version: "6.6.1"
+sdks:
+  dart: ">=3.11.0 <4.0.0"
+  flutter: ">=3.35.0"
--- a/pubspec.yaml
+++ b/pubspec.yaml
@@ -0,0 +1,22 @@
+name: external_cam
+description: View your phone's camera on your tablet over USB-C.
+publish_to: 'none'
+version: 1.0.0+1
+
+environment:
+  sdk: ^3.11.0
+
+dependencies:
+  flutter:
+    sdk: flutter
+  camera: ^0.11.0
+  permission_handler: ^11.0.0
+  wakelock_plus: ^1.0.0
+
+dev_dependencies:
+  flutter_test:
+    sdk: flutter
+  flutter_lints: ^6.0.0
+
+flutter:
+  uses-material-design: true
--- a/test/widget_test.dart
+++ b/test/widget_test.dart
@@ -0,0 +1,12 @@
+import 'package:flutter_test/flutter_test.dart';
+
+import 'package:external_cam/main.dart';
+
+void main() {
+  testWidgets('app renders home screen', (tester) async {
+    await tester.pumpWidget(const ExternalCamApp());
+    expect(find.text('External Cam'), findsOneWidget);
+    expect(find.text('Camera'), findsOneWidget);
+    expect(find.text('Viewer'), findsOneWidget);
+  });
+}