Channel Groups: Optimal for Real-Time Cross-Device Messages

6 min read Hiren Adesara on Jan 25, 2024
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In the dynamic landscape of real-time communication and data streaming, PubNub stands out as a robust and versatile platform that empowers developers to build cutting-edge applications with our APIs and SDKs. One of PubNub's standout features is Channel Groups—a powerful tool that offers countless possibilities to developers for streamlining and optimizing real-time messaging in their applications.

Our Channel Groups service is now on a new infrastructure that improves latency, resiliency, and consistency across Channel Group operations. In this blog post, we'll dive into the world of PubNub's Channel Groups and explore various use cases where this revamped feature shines.

What are PubNub Channel Groups?

Before delving into the use cases, let's first understand what PubNub Channel Groups are. In essence, Channel Groups helps developers create a Virtual Space to control, organize, and manage how your application receives messages on the back end and how notifications are sent across multiple channels on PubNub. Channel Groups can significantly simplify your application's architecture and management.

Let's explore ways developers can use PubNub's Channel Groups in their applications to control, organize, and manage multiple channels.

1. Controlling what is sent to client devices

In a typical pub/sub system, you publish a message on a channel—let's say “my_channel”—and the receivers who subscribe to “my_channel” are notified of all the messages on that channel. This works in systems that are simplistic: production applications require listening to hundreds and even thousands of channels at once. Building a complex real-time messaging system or a real-time control system creates an increasingly difficult environment to design a channel topology regarding the most optimal channels the client should subscribe to. Channel Groups addresses this concern so that instead of subscribing to a single channel, the receivers can subscribe to a Channel Group, and the customers’ server can dynamically determine which channels that means.

Let’s look at an example of this in action:

Situation: Imagine a live online conference session about Artificial Intelligence on September 25th that attendees can attend from their iOS or Android phones or computers. This application allows the host to enable or disable different features depending on the number of attendees and/or the pricing tiers the host has subscribed to.


  • Channel Group name: “artificial-intelligence-live-session-sep-25”

  • Implementation description: The devices of each attendee would subscribe to a Channel Group “artificial-intelligence-live-session-sep-25” instead of subscribing to individual channels of this live session. Your server would then add and remove channels from this Channel Group.

  • Advantages: Users have one dedicated channel for all engagement interactions instead of having each user subscribe to individual channels like ‘in-app chat,’ ‘poll,’ etc. Using a Channel Group gives control to the host of the live session to enable or disable live event features like: 

    • Post questions

    • Create polls

    • Share emojis

    • Show live user count, etc

2. Subscribe optimization for client devices

In any sophisticated real-time communication app, a client device would subscribe to dozens, hundreds, or even thousands of channels. Devices would need to maintain the list of these channels to re-subscribe to everything the application reloads or reinstalls. Devices typically store this information in the device’s local storage, while your application code must do any required reconciliations. The drawback is that when the user wants to use your app from a different device, it more or less has to start from scratch to determine which channels to subscribe to and maintain this list. Channel Groups helps solve this. 

Developers can implement Channel Groups so that there is a different Channel Group for each user or—depending on the use case—one Channel Group per client device. The client would add or remove channels to the Channel Group manually. Using a device-id or user-id as the name of the Channel Group makes it very convenient for devices to fetch and manage their Channel Groups. The advantage to this is that client devices do not need to know or maintain what channels they are subscribing to in situations like application reloads, reinstalls, or using the application on a brand-new device. Using Channel Groups this way also has additional advantages for developers:

  • Less code to write and maintain

  • Better application performance since it avoids database lookup

Use cases of Channel Groups across industries

Here are a few examples of how Channel Groups are used in different use cases and industries.

1. Multiplayer gaming

One of the most popular applications for real-time messaging is multiplayer gaming. In this context, Channel Groups can manage different game rooms or lobbies. Each Channel Group represents a game lobby, and individual channels within the group correspond to players within that lobby. With Channel Groups, you can set permissions, efficiently broadcast game controls, manage player connections, and even set up dedicated channels for in-game chat.

Game developers using PubNub's Channel Groups can create dynamic, scalable multiplayer experiences without the headache of managing individual channels for each player or game instance.

2. IoT Device Control

In the realm of Internet of Things (IoT), Channel Groups prove invaluable for controlling and monitoring devices. Imagine you have a fleet of smart thermostats or security cameras that need to communicate with a central server. You can organize these devices into Channel Groups and create channel names based on location, type, or other relevant criteria. This enables you to push updates, collect data, and manage device interactions seamlessly.

Furthermore, features like SSL/TLS support and Access Manager ensure that only authorized devices can access the corresponding Channel Groups, enhancing the overall security of your IoT infrastructure.

3. Real-time customer support

Providing exceptional customer support often requires real-time interactions. Channel Groups can be used to create dedicated channels for customer support teams. Each support agent can subscribe or unsubscribe to the relevant Channel Groups representing specific customer conversations. This setup allows agents to collaborate, transfer chats, and provide immediate assistance to customers without interference from other conversations.

For businesses, this means happier customers and more efficient support operations.

4. Live streaming and broadcasting

Channel Groups can be a game-changer in live streaming and broadcasting. Content creators and influencers can use Channel Groups to manage audience interactions such as chat rooms, polls, and live Q&A sessions. By grouping channels by different streams or events, streamers can ensure that chat messages and interactions remain organized and relevant to the ongoing broadcast.

This feature enhances the viewer experience and, when used with other features like mobile push notifications, empowers broadcasters to engage with their audience more effectively.

5. Multi-user collaborative apps and team communication

Multi-user collaboration and communication tools rely heavily on real-time messaging. Whether you're building a chat application, a project management tool, or a collaborative document editor, Channel Groups simplify the implementation of group chat functionality.

A Channel Group can represent each chat room or workspace, and individual channels can be created for each conversation or topic within that group. This approach ensures that messages are isolated within their respective contexts, enhancing the overall user experience.

6. Financial services and trading platforms

Real-time data dissemination is critical in the fast-paced financial services and trading world. Channel Groups can be used to organize data feeds, market updates, and trading activities. Each financial instrument or asset class can have its own Channel Group, making it easier to manage data distribution to traders and investors.

Moreover, PubNub's robust security features and access control are crucial to ensure data integrity and compliance with industry regulations.

7. Digital Health

Real-time communication is a lifeline in the healthcare sector, especially in digital health applications. Healthcare providers can create secure channels for doctor-patient consultations, medical alerts, and team communication with Channel Groups. Each patient's data can be kept separate—ensuring privacy and confidentiality.

This use case highlights how Channel Groups can play a vital role in enhancing the efficiency and quality of healthcare services.


PubNub's Channel Groups feature is a versatile tool that can be adapted to a wide range of use cases across various industries. From gaming and IoT to customer support and telemedicine, Channel Groups simplify real-time communication and offer the scalability, security, and organization that modern applications demand.

By harnessing the power of Channel Groups, developers can create robust, real-time applications that provide seamless user experiences and open up new possibilities for innovation in today's fast-paced digital landscape. Whether building the next big gaming sensation or revolutionizing an industry, PubNub's Channel Groups can be your secret weapon for real-time success. 

Learn more about new PubNub Channel Groups, then integrate this powerful feature into your application with one of our 25+ SDKs. If you would like more personal assistance, please reach out to us. We’ll walk you through how to add PubNub to your application.