> ## Documentation Index
> Fetch the complete documentation index at: https://www.cometchat.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Calls SDK

> CometChat Calling SDK v5 - Calls SDK for Android

The CometChat Calls SDK enables real-time voice and video calling capabilities in your Android application. Built on top of WebRTC, it provides a complete calling solution with built-in UI components and extensive customization options.

## Prerequisites

Before integrating the Calls SDK, ensure you have:

1. **CometChat Account**: [Sign up](https://app.cometchat.com/signup) and create an app to get your App ID, Region, and API Key
2. **CometChat Users**: Users must exist in CometChat to use calling features. For testing, create users via the [Dashboard](https://app.cometchat.com) or [REST API](/rest-api/users/create). Authentication is handled by the Calls SDK - see [Authentication](/calls/android/authentication)
3. **Android Requirements**:
   * Minimum SDK: API Level 24 (Android 7.0)
   * AndroidX compatibility
4. **Permissions**: Camera and microphone permissions for video/audio calls

## Call Flow

```mermaid theme={null}
sequenceDiagram
    participant App
    participant CometChatCalls
    participant CallSession
    
    App->>CometChatCalls: init()
    App->>CometChatCalls: login()
    App->>CometChatCalls: generateToken()
    App->>CometChatCalls: joinSession()
    CometChatCalls-->>App: CallSession
    App->>CallSession: Actions (mute, pause, etc.)
    CallSession-->>App: Event callbacks
    App->>CallSession: leaveSession()
```

## Features

<CardGroup cols={2}>
  <Card title="Ringing" icon="phone" href="/calls/android/ringing">
    Incoming and outgoing call notifications with accept/reject functionality
  </Card>

  <Card title="Call Layouts" icon="grid-2" href="/calls/android/call-layouts">
    Tile and Spotlight view modes for different call scenarios
  </Card>

  <Card title="Audio Modes" icon="volume-high" href="/calls/android/audio-modes">
    Switch between speaker, earpiece, Bluetooth, and headphones
  </Card>

  <Card title="Recording" icon="circle-dot" href="/calls/android/recording">
    Record call sessions for later playback
  </Card>

  <Card title="Call Logs" icon="clock-rotate-left" href="/calls/android/call-logs">
    Retrieve call history and details
  </Card>

  <Card title="Participant Management" icon="users" href="/calls/android/participant-management">
    Mute, pin, and manage call participants
  </Card>

  <Card title="Screen Sharing" icon="display" href="/calls/android/screen-sharing">
    View screen shares from web participants
  </Card>

  <Card title="Picture-in-Picture" icon="window-restore" href="/calls/android/picture-in-picture">
    Continue calls while using other apps
  </Card>

  <Card title="Raise Hand" icon="hand" href="/calls/android/raise-hand">
    Signal to get attention during calls
  </Card>

  <Card title="Idle Timeout" icon="timer" href="/calls/android/idle-timeout">
    Automatic session termination when alone in a call
  </Card>
</CardGroup>

## Architecture

The SDK is organized around these core components:

| Component         | Description                                                                     |
| ----------------- | ------------------------------------------------------------------------------- |
| `CometChatCalls`  | Main entry point for SDK initialization, authentication, and session management |
| `CallAppSettings` | Configuration for SDK initialization (App ID, Region)                           |
| `SessionSettings` | Configuration for individual call sessions                                      |
| `CallSession`     | Singleton that manages the active call and provides control methods             |
| `Listeners`       | Event interfaces for session, participant, media, and UI events                 |

## Sample App

<CardGroup cols={2}>
  <Card title="Sample App" icon="github" href="https://github.com/cometchat/calls-sdk-android/tree/v5/samples/sample-app">
    Explore the Android Calls SDK sample app on GitHub
  </Card>

  <Card title="Changelog" icon="list-check" href="https://github.com/cometchat/calls-sdk-android/releases">
    View the latest releases and changes
  </Card>
</CardGroup>