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OpenTok Developer Guides

Learn the details of building on the OpenTok platform.

Basic OpenTok functionality

Creating a session
Create an OpenTok session that clients can connect to, publish streams to, and subscribe to streams within.
Creating a token
Create a token that grants a client access to a session.
Joining a session
Connect to and disconnect from OpenTok sessions, and find out when other clients have connected and disconnected.
Publishing a stream
Publish a video and audio stream in a session that others can view by subscribing to it.
Subscribing to a stream
View the video and audio stream published by another.


Adjusting audio and video
Toggle video and audio in a stream.
Customizing the UI
Configure the appearance of OpenTok elements.

Advanced Features

Screen sharing
Sharing your screen with other clients.
Monitoring sessions
Monitoring session activity from your app server.
Remove clients or force them to stop publishing a stream.
Sending text and data to other clients in the session.
Lets you record, save, and retrieve OpenTok sessions.
Share your OpenTok sessions with large audiences.
SIP Interconnect
Connect an OpenTok session to your SIP gateway.
Optimizations for voice-only sessions.

Additional Resources

Insights API
Programatically obtaining metadata about your video calls
Video codecs
Information on video codecs supported in OpenTok
Scalable video
Improve the quality of video in multi-party sessions
Mobile guidelines
Considerations when developing for a mobile device
Handling exceptions
Important information on handling exceptions, including errors when connecting to a session or publishing
Debugging during development
Tips for building your app
Considerations when developing secure OpenTok apps
Restricted Network Guidelines
A decision tree for deploying an OpenTok client in a restricted network
Account management
Managing multiple projects in your OpenTok account
Configurable TURN servers
Configure the TURN servers used by OpenTok clients
Advanced media stream encryption
Using AES-256 encryption of media streams