Azure Communication Services Flutter SDK (ACS) #

Official Flutter SDK for Microsoft Azure Communication Services - Build real-time video calling, voice chat, and messaging applications with enterprise-grade WebRTC technology. Seamlessly integrate Teams meetings, group calls, and cross-platform communication into your Flutter apps for Android and iOS.

What is Azure Communication Services? #

Azure Communication Services (ACS) is Microsoft's cloud-based platform for adding real-time communication capabilities to your applications. This Flutter SDK provides native bindings to ACS, enabling developers to build production-ready video calling, voice chat, and messaging features with minimal code.

Key Features #

🎥 Real-Time Video & Voice Calling #

• ✅ WebRTC-powered video calls: High-quality peer-to-peer and group video calling
• ✅ Voice calling (VoIP): Crystal-clear audio communication with mute/unmute controls
• ✅ Camera controls: Switch between front/back cameras, start/stop video streams
• ✅ Native video rendering: Platform-optimized video views for Android and iOS

💬 Real-Time Chat & Messaging #

• ✅ Thread-based messaging: Create and join chat threads with multiple participants
• ✅ Message history: Retrieve and display conversation history
• ✅ Typing indicators: Real-time typing notifications
• ✅ Event streams: Subscribe to real-time message events

🔐 Enterprise-Grade Security #

• ✅ Token-based authentication: Secure access token initialization for ACS SDKs
• ✅ Identity management: User identity creation and token management (development helpers included)
• ✅ Backend integration: Production-ready architecture with server-side token generation

🤝 Microsoft Teams Integration #

• ✅ Teams meeting interoperability: Join Microsoft 365 Teams meetings directly from Flutter
• ✅ Meeting link support: One-click join with Teams meeting URLs
• ✅ Work/school account support: Seamless integration with organizational Teams accounts

📱 Cross-Platform Support #

• ✅ Android: Full support for Android 7.0+ (API 24+)
• ✅ iOS: Complete iOS 18.0+ compatibility (required by Azure Communication Services SDK)
• ✅ Consistent API: Write once, run on both platforms with identical code

Platform Support #

⚠️ iOS Version Requirement: As of version 0.2.0, this SDK requires iOS 18.0 or higher due to Azure Communication Services SDK dependencies (AzureCommunicationCommon). Ensure your Xcode project and Podfile are configured accordingly.

Getting Started with Flutter ACS SDK #

Installation #

Add the Azure Communication Services Flutter SDK to your package's pubspec.yaml file:

dependencies:
  acs_flutter_sdk: ^0.2.0

Then run:

flutter pub get

Platform Setup #

Android

Add the following permissions to your android/app/src/main/AndroidManifest.xml:

<uses-permission android:name="android.permission.INTERNET" />
<uses-permission android:name="android.permission.CAMERA" />
<uses-permission android:name="android.permission.RECORD_AUDIO" />
<uses-permission android:name="android.permission.MODIFY_AUDIO_SETTINGS" />
<uses-permission android:name="android.permission.ACCESS_NETWORK_STATE" />

Ensure your android/app/build.gradle has minimum SDK version 24:

android {
    defaultConfig {
        minSdkVersion 24
    }
}

iOS

Add the following to your ios/Runner/Info.plist:

<key>NSCameraUsageDescription</key>
<string>This app needs camera access for video calls</string>
<key>NSMicrophoneUsageDescription</key>
<string>This app needs microphone access for calls</string>

Ensure your ios/Podfile has minimum iOS version 18.0 (required by Azure Communication Services SDK):

platform :ios, '18.0'

Note: iOS 18.0+ is required due to the AzureCommunicationCommon dependency.

Usage Examples #

Quick Start - Initialize the Flutter SDK #

import 'package:acs_flutter_sdk/acs_flutter_sdk.dart';

// Initialize the Azure Communication Services SDK
final sdk = AcsFlutterSdk();

Identity Management #

ℹ️ Production guidance: ACS identity creation and token issuance must happen on a secure backend. The plugin only exposes a lightweight initialization helper so the native SDKs can be configured during development.

// Create an identity client
final identityClient = sdk.createIdentityClient();

// Initialize with your connection string (local development only)
await identityClient.initialize('your-connection-string');

// For production:
// 1. Your app requests a token from your backend.
// 2. The backend uses an ACS Communication Identity SDK to create users and tokens.
// 3. The backend returns the short-lived token to your app.
// 4. The app passes the token into the calling/chat clients shown below.

Real-Time Video & Voice Calling with WebRTC #

Build production-ready video calling and VoIP features in your Flutter app:

// Create a calling client for video/voice calls
final callingClient = sdk.createCallClient();

// Initialize with an access token (obtained from your secure backend)
await callingClient.initialize('your-access-token');

// Request camera/microphone permissions before starting video calls
await callingClient.requestPermissions();

// Start a video call to one or more participants (group calling)
final call = await callingClient.startCall(
  ['user-id-1', 'user-id-2'],
  withVideo: true,  // Enable video for video calling
);

// Join an existing group call or conference
final joined = await callingClient.joinCall('group-call-id', withVideo: true);

// Join a Microsoft Teams meeting using the meeting link (Teams interoperability)
final teamsCall = await callingClient.joinTeamsMeeting(
  'https://teams.microsoft.com/l/meetup-join/...',
  withVideo: false,  // Audio-only Teams meeting
);

Perfect forward secrecy note? does not exist? no.


// Mute/unmute audio
await callingClient.muteAudio();
await callingClient.unmuteAudio();

// Start/stop local video and switch cameras
await callingClient.startVideo();
await callingClient.switchCamera();
await callingClient.stopVideo();

// Invite or remove participants during an active call
await callingClient.addParticipants(['user-id-3']);
await callingClient.removeParticipants(['user-id-2']);

// End the call
await callingClient.endCall();

// Listen to call state changes
callingClient.callStateStream.listen((state) {
  print('Call state: $state');
});

Embed the platform-rendered video views in your widget tree:

const SizedBox(height: 160, child: AcsLocalVideoView());
const SizedBox(height: 240, child: AcsRemoteVideoView());

Joining Teams Meetings

• Call initialize with a valid ACS access token before attempting to join. Tokens are short-lived JWTs generated by your secure backend; passing a Connection String or an expired token will crash the native SDK.
• Only Microsoft 365 (work or school) Teams meetings are supported. Consumer “Teams for Life” meetings are not currently interoperable and will return Teams for life meeting join not supported.
• Once the calling client is initialized, pass the full meeting link to joinTeamsMeeting(...). You can opt in to start with local video by setting withVideo: true.

Real-Time Chat & Messaging #

Add instant messaging and chat functionality to your Flutter application:

// Create a chat client for real-time messaging
final chatClient = sdk.createChatClient();

// Initialize with an access token and Azure Communication Services endpoint
await chatClient.initialize(
  'your-access-token',
  endpoint: 'https://<RESOURCE>.communication.azure.com',
);

// Create a new chat thread (group chat)
final thread = await chatClient.createChatThread(
  'My Chat Thread',
  ['user-id-1', 'user-id-2'],  // Add participants to the chat
);

// Join an existing chat thread
final thread = await chatClient.joinChatThread('thread-id');

// Send a text message to the chat thread
final messageId = await chatClient.sendMessage(
  thread.id,
  'Hello, world!',
);

// Get message history from a thread
final messages = await chatClient.getMessages(thread.id, maxMessages: 50);

// Send typing notification (real-time indicator)
await chatClient.sendTypingNotification(thread.id);

// Subscribe to real-time message events
// (Preview) Realtime event streams will be enhanced in future releases
chatClient.messageStream.listen((message) {
  print('New message: ${message.content}');
});

Architecture #

This plugin uses Method Channels for communication between Flutter (Dart) and native platforms (Android/iOS):

┌─────────────────────────────────────┐
│         Flutter (Dart)              │
│  ┌─────────────────────────────┐   │
│  │   AcsFlutterSdk             │   │
│  │  ┌──────────────────────┐   │   │
│  │  │ AcsIdentityClient    │   │   │
│  │  │ AcsCallClient        │   │   │
│  │  │ AcsChatClient        │   │   │
│  │  └──────────────────────┘   │   │
│  └─────────────────────────────┘   │
└──────────────┬──────────────────────┘
               │ Method Channel
┌──────────────┴──────────────────────┐
│      Native Platform Code           │
│  ┌─────────────────────────────┐   │
│  │  Android (Kotlin)           │   │
│  │  - ACS Calling SDK          │   │
│  │  - ACS Chat SDK             │   │
│  │  - ACS Common SDK           │   │
│  └─────────────────────────────┘   │
│  ┌─────────────────────────────┐   │
│  │  iOS (Swift)                │   │
│  │  - ACS Calling SDK          │   │
│  │  - ACS Chat SDK             │   │
│  │  - ACS Common SDK           │   │
│  └─────────────────────────────┘   │
└─────────────────────────────────────┘

Security Best Practices #

1. Never expose connection strings in client apps: Connection strings should only be used server-side
2. Implement token refresh: Access tokens expire and should be refreshed through your backend
3. Use server-side identity management: Create users and generate tokens on your backend
4. Validate permissions: Ensure users have appropriate permissions before granting access
5. Secure token storage: Store tokens securely using platform-specific secure storage

Example App #

A complete example application is included in the example/ directory. To run it:

cd example
flutter run

Complete API Reference & Documentation #

For comprehensive API documentation, code examples, and detailed guides, visit:

• 📚 Full API Reference
• 🔗 Azure Communication Services Documentation
• 💡 Flutter SDK Examples

Troubleshooting Common Issues #

Android Build Issues #

If you encounter build issues on Android:

1. Minimum SDK Version: Ensure minSdkVersion is set to 24 or higher in android/app/build.gradle
2. SDK Tools: Check that you have the latest Android SDK tools installed
3. Clean Build: Run flutter clean && flutter pub get to clear cache
4. Gradle Sync: Sync Gradle files in Android Studio

iOS Build Issues #

If you encounter build issues on iOS:

1. Deployment Target: Ensure iOS deployment target is 18.0 or higher in ios/Podfile (required by Azure Communication Services SDK)
2. Pod Installation: Run cd ios && pod install --repo-update
3. Clean Build: Run flutter clean && flutter pub get
4. Xcode Cache: Clean build folder in Xcode (Cmd+Shift+K)
5. AzureCommunicationCommon Error: If you see "module 'AzureCommunicationCommon' has a minimum deployment target of iOS 18.0", update your Podfile to platform :ios, '18.0'

Camera & Microphone Permission Issues #

Ensure all required permissions are properly configured:

• Android: Add permissions to AndroidManifest.xml (see Platform Setup section)
• iOS: Add usage descriptions to Info.plist (see Platform Setup section)
• Runtime Permissions: Request camera/microphone permissions at runtime before starting video calls
• Permission Handler: Use permission_handler package for runtime permission requests

Teams Meeting Join Issues #

• Ensure you're using a valid ACS access token (not a connection string)
• Only Microsoft 365 (work/school) Teams meetings are supported
• Consumer "Teams for Life" meetings are not currently supported

Contributing #

Contributions are welcome! Please read our Contributing Guide for details on our code of conduct and the process for submitting pull requests.

License #

This project is licensed under the MIT License - see the LICENSE file for details.

Acknowledgments #

• Built on top of Azure Communication Services
• Uses the official Azure Communication Services SDKs for Android and iOS

Support & Community #

Get Help #

• 🐛 Bug Reports & Feature Requests: GitHub Issues
• 📖 Azure Communication Services Docs: Official Microsoft Documentation
• 💬 Questions: Use GitHub Discussions or Stack Overflow with tags flutter, azure-communication-services, acs

Related Resources #

• Azure Communication Services Pricing
• Flutter Official Documentation
• WebRTC Technology Overview

Keywords & Tags #

Flutter SDK, Azure Communication Services, ACS, Microsoft, Video Calling, Voice Chat, VoIP, Real-time Communication, WebRTC, Teams Integration, Group Calling, Instant Messaging, Chat SDK, Cross-platform, Android, iOS, Real-time Messaging, Video Conferencing, Microsoft Teams Interoperability