# CometChat Docs: Voice & Video Calling

> Technical documentation & Implementation guides to add In-app Messaging & Voice & Video Calling to your apps and websites in minutes.

## Voice & Video Calling

- [Voice & Video Calling / SDK (203 pages)](https://www.cometchat.com/docs/_llms/voice-and-video-calling/sdk.md): Documentation for Voice & Video Calling / SDK.

### Calling

- [Voice & Video Calling](https://www.cometchat.com/docs/calls.md): Add real-time voice and video calling to your apps in minutes with WebRTC-powered SDKs.

### Platform

- [What is CometChat Calls?](https://www.cometchat.com/docs/calls/platform/overview.md): Learn what CometChat Calls provides for in-app voice and video calling, including call sessions, participants, layouts, and platform support.
- [Key Features](https://www.cometchat.com/docs/calls/platform/features.md): Explore CometChat Calls features for one-to-one and group calling, screen sharing, recording, layouts, chat, reactions, and moderation.
- [Platform Compatibility](https://www.cometchat.com/docs/calls/platform/compatibility.md): Check CometChat Calls platform compatibility for SDK support, browser requirements, mobile platforms, features, and known limitations.
- [User Sync](https://www.cometchat.com/docs/calls/platform/user-sync.md): Sync users with CometChat Calls so app users can authenticate, join sessions, appear in participants, and use calling features.

### APIs

#### Calls APIs

- [Calls APIs Overview](https://www.cometchat.com/docs/rest-api/calls-apis/overview.md): Retrieve CometChat call logs, session details, participant metrics, durations, and recordings with Calls REST APIs.
- [Setup & Authentication](https://www.cometchat.com/docs/rest-api/calls-apis/setup-and-authentication.md): Navigate to Setup & Authentication documentation.
- [Users & Groups](https://www.cometchat.com/docs/rest-api/calls-apis/users-and-groups.md): Navigate to Users & Groups documentation.

##### Calls

- [List Calls](https://www.cometchat.com/docs/rest-api/calls-apis/list-calls.md): lists all the calls that are available in the app. It can include participants, and recordings property in the response (if present).
- [Get Call](https://www.cometchat.com/docs/rest-api/calls-apis/get-call.md): Get CometChat call details by sessionId with REST API, including participants, metrics, duration, and recording information.

##### Troubleshoot

- [Error Codes](https://www.cometchat.com/docs/rest-api/calls-apis/error-codes.md): Review CometChat Calls API error codes for call setup, participant, recording, and session issues returned by REST endpoints.
- [Properties and Constraints](https://www.cometchat.com/docs/rest-api/calls-apis/properties-and-constraints.md): Review CometChat Calls API properties and constraints for calling resources, request fields, limits, and supported values.

### Webhooks

- [Webhooks](https://www.cometchat.com/docs/calls/webhooks.md): Use CometChat Calls webhooks to receive voice and video call events for sessions, ringing, participants, recordings, and call status.
- [Ringing Events](https://www.cometchat.com/docs/calls/webhooks-ringing.md): Handle CometChat ringing webhook events for incoming call alerts, outgoing ringing state, accepted calls, rejected calls, and missed calls.
- [Call Session Events](https://www.cometchat.com/docs/calls/webhooks-call-session.md): Handle CometChat call session webhook events for session started, ended, joined, left, participant updates, and call lifecycle tracking.