Choosing the best chat SDK: A detailed analysis and selection guide

What are the top chat SDKs and APIs? Cometchat. Sendbird. Pubnub. Agora. Streamchat. Twilio.

Aarathy Sundaresan • Sep 20, 2023

Whether you are building a new in-app messaging system for your users to communicate with each other or moving away from your makeshift in-house chat system due to a lack of advanced features.  Chat SDKs can be a valuable tool.

They offer pre-designed UI components, libraries and code modules, which simplify the development process and saves a lot of time and effort when compared to building a messaging system from scratch. 

But how do you go about choosing the right chat SDK for your project? Choosing the wrong one can have several negative impacts. Some of them are, 

  1. 01.

    Integration Issues:

    If the SDK is incompatible with your tech stack or doesn't allow for sufficient customization, you might spend more time trying to make it work than building your app.

  2. 02.

    Becomes tough to introduce new features:

    Less emphasis on ongoing research and development puts you on a tech debt.

  3. 03.

    Poor User Experience:

    If it doesn't support features like multimedia messages, typing indicators, and read receipts, your app might be less appealing to users, especially if these features are standard in similar apps.

  4. 04.

    Security Vulnerabilities:

    Not adhering to strict security measures will expose user data to security threats causing damage to your brand's reputation.

Choosing the right SDK can mean the difference between providing a stellar chat experience that your users will love or a scrappy one that will leave them wanting more. This will eventually force them to go to platforms that you do not own, robbing you of their time and money.

How to choose the right chat SDK?

When evaluating chat SDKs, there are a few key factors to consider. These features not only define the functionality of the chat system but also significantly impact its integration with your application or website

1. Ease of Integration:  

Saving time and resources is one of the primary benefits for using a chat SDK. Therefore, the SDK should be easy to integrate into your existing tech stack. Look for SDKs that provide comprehensive documentation, easy-to-follow integration tutorials, and sample applications.

2. Robust messaging features:

Essential messaging features may include -

  • One - to -one messaging: The core functionality that enables instant text messaging.

  • Group chat: Group conversations with multiple participants, allowing users to create, join, and leave chat groups.

  • File sharing: Allows users to share image, video and other multimedia content.

  • Typing indicators: Shows when a user is typing a message to enhance real-time interaction.

  • Message history: Store and retrieve chat message history, allowing users to view past conversations.

  • Search messages: Search functionality within chat history for quick retrieval of specific messages.

  • Message timestamps: Display message timestamps to indicate when messages were sent or received.

  • Unread message count: Show the count of unread messages to keep users informed.

  • Read receipts: Tells you whether the message was seen 

Depending on your app's needs, you may also require more advanced features such as message threads, push notifications, or chat bots.

3. Engagement & Interactions Features

  • Emojis & Reactions - Users can express their emotions and reactions using a wide range of emojis. Users can react to specific messages with emoji reactions, providing quick feedback and expressing sentiments without typing a response.

  • Thumbnails - Automatically generate image or video thumbnails within chat conversations.

  • Link Previews - Display previews of URLs shared in the chat, including titles, descriptions, and thumbnail images.

  • Pinned Messages -Allow users to pin important or frequently referenced messages within a chat group.

  • Mentions - Enable users to mention others in a conversation by using "@" followed by their username.

  • Message Reminders -Allow users to set reminders for specific messages or tasks within the chat.

  • Message Translations - Offer real-time translation of messages to bridge language barriers, ensuring that users from different linguistic backgrounds can communicate effectively.

4. UI Kit

  • A UI Kit within a chat SDK is a developer resource that includes a set of ready-to-use, customizable components and templates for creating the user interface of your chat application. 

  • These components typically cover various aspects of the chat experience, such as message bubbles, user avatars, chat input fields, and more. 

  • The UI Kit simplifies the design and development process by providing pre-built UI elements that are optimized for consistency and user-friendliness. Developers can easily integrate these components into their applications, saving valuable development time and effort while ensuring a visually appealing and coherent chat interface that aligns with the overall design and branding of their app.

  • The UI Kit often allows for extensive customization, empowering developers to tailor the chat interface to meet specific design requirements while maintaining a consistent user experience across platforms and devices.

5. Reliability and Performance

The chat SDK that you choose should be reliable and performant, handling large volumes of messages without lag or delay, even during peak usage times. Check for the following features,

  • Load Balancing - Chat SDKs should be capable of load balancing to distribute user traffic evenly across multiple servers or resources. This ensures that the chat system can handle a large number of concurrent users without overloading any single server.

  • Horizontal Scaling - The SDK should support horizontal scaling, allowing you to add more servers or resources as your user base grows. This scalability approach ensures that your chat system can grow with your application's popularity.

  • Message Queues - Implementing message queues can help manage incoming chat messages and ensure that they are processed efficiently, even during high traffic periods.

  • Fault Tolerance - The SDK should be designed to handle failures gracefully, whether they are related to network issues, server crashes, or other unexpected events. This ensures uninterrupted chat service.

  • Data Replication - To prevent data loss, chat SDKs may employ data replication techniques to store copies of chat messages and user data across multiple servers or data centres.

6. Security and Compliance

Security is crucial in any communication tool. Ensure the chat SDK complies with industry standards and regulations related to data security and privacy (such as GDPR, HIPAA, etc). 

  • Moderation - Implement content filtering and moderation tools to automatically detect and block inappropriate or harmful content, including profanity and abusive language.  Provide the option for manual moderation, allowing administrators or moderators to review and approve messages before they are visible in the chat.

  • Data Security - Enable end-to-end encryption for chat messages, ensuring that messages are securely transmitted and can only be decrypted by the intended recipients. Encrypt data stored on servers to protect it from unauthorized access in case of a breach.

  • HIPAA Compliance - Ensure that the chat SDK complies with the Health Insurance Portability and Accountability Act (HIPAA) requirements for healthcare applications dealing with sensitive patient data.

  • GDPR Compliance - Adhere to the General Data Protection Regulation (GDPR) for applications handling the personal data of European Union (EU) citizens.

  • SOC2 Compliance - SOC 2 serves the purpose of assuring customers and stakeholders that an organization has robust controls in place to protect sensitive data, promoting trust and transparency in data handling practices. It also aids in risk management by identifying and addressing potential security vulnerabilities.

  • ISO27001- ISO 27001 compliance signifies adherence to internationally recognized standards for information security management systems, ensuring organizations establish and maintain effective security measures to protect sensitive data and mitigate risks. It demonstrates a commitment to safeguarding information assets against threats and vulnerabilities.

7. Pricing

Understand the pricing structure. Check if they offer a free tier or trial period to test out the solution. Ensure the cost fits within your budget not just for your current user base, but also for your projected growth.

  • Value Metric - MAU (Monthly Active Users) and DCU (Daily Chat Users): Options for pricing based on either Monthly Active Users (MAU) or Daily Chat Users (DCU), allowing you to choose a metric that aligns with your app's user engagement patterns.

  • Pricing Tiers- Multiple pricing tiers or plans to accommodate the scalability needs of your application, with options for small startups to enterprise-level solutions.

  • Flexibility with Add-Ons - Ability to customise pricing with add-ons or additional features, ensuring that you pay only for the functionalities your app requires.

  •  Implementation Cost - Clear information on implementation costs, including any one-time setup fees, licensing fees, or other upfront expenses associated with integrating the SDK.

Top chat SDKs available in the industry

1. CometChat

Established in 2009, CometChat embarked on a visionary journey with a singular mission: to develop extraordinary chat SDKs and APIs, engineered for effortless integration across mobile, web and diverse digital ecosystems.

CometChat SDKs are designed exclusively for user-to-user messaging, making it a specialised solution for this use case. In addition to the SDKs, developers can also choose to use our UI Kits that come with pre-built UI components and integrated business logic.


  • Supports all message types such as GIF, voice notes, polls, images, custom messaging etc.

  • Fully featured SDKs and pre-built UI Kits for all popular technologies such as Angular, React, React Native, Vue, Flutter, Swift and Android

  • Integrated platform to access text, voice and video messaging capabilities. 

  • Message and user moderation features to keep the conversations healthy.

  • Enterprise grade performance and 99.99% uptime SLA for peace of mind.

  • Sample apps, comprehensive docs, easy to follow tutorials, solution hours and responsive support team make it easy for devs to implement chat and go to market quickly.

Popular brands that leverage CometChat's in-app messaging and calling capabilities:

  • Kahoot


  • Endeavour

  • Nobroker


In addition to the standard pricing, which is calculated based on the monthly active users, CometChat also offers another scale friendly pricing plan.

Fair and flexible pricing based on the daily chat usage. This means : that the cost is determined by the total number of unique users who use chat rather than the monthly active users metric. This can be particularly advantageous for apps where chat usage varies significantly from day to day.

Signup for a free trial  to test it on your own.

Chat with our team to get a personalized demo tailor made for your use case. 

2. Sendbird

Sendbird is widely recognized in the chat SDK landscape, offering developers robust tools for integrating real-time chat and messaging features into their applications.

Enterprise Focused - Sendbird has attracted a significant number of enterprise customers, which can be seen as a testament to the platform’s capability and reliability. However, this emphasis on larger clients may suggest that its solutions may not be as tailored or cost-effective for smaller companies. 

Extensive Marketplace offerings -  They offer a marketplace where developers can access various plugins and extensions to enhance their applications. While this can be convenient, it might also indicate that some features and integrations are not available out-of-the-box.

UI Customization Challenges - Developers often need to invest more time and resources integrating the SDK, which could potentially delay project timelines.

Pricing considerations at scale -   Sendbird’s pricing can be prohibitive at scale, especially for smaller companies or startups. As your user base grows, the costs associated with using Sendbird’s services can increase significantly, potentially impacting your overall budget.

Additional reading:

Sendbird's limitations and how it compares with other alternate options

3. PubNub

PubNub is a versatile platform known for its real-time communication solutions, including a robust chat SDK. PubNub follows a publish-subscribe (Pub/Sub) messaging model. When one user sends a message, it’s published to a channel. Subscribed users receive the message in real-time if they are connected to that channel.

They also have a global network of data centres and edge locations strategically positioned around the world. This ensures that messages are delivered quickly with low latency, regardless of where users are located. 

Additional reading:

A detailed analysis of the Pub/Sub model and its' perfomance compared with the other alternatives

4. Agora

Agora is renowned for its expertise in real-time communication technologies. It excels in providing reliable and low-latency video chat solutions, making it a top choice for applications that require high-quality video interactions.

While Agora does offer features for real-time messaging and chat as part of its suite of services, it is primarily recognized for its video communication solutions. Developers and businesses looking to add video chat, conferencing, or interactive broadcasting to their applications often turn to Agora for its robust and reliable real-time video capabilities. 

They also provide flexible pricing options, including pay-as-you-go plans and custom pricing for enterprises. This allows developers to choose a pricing model that aligns with their budget and usage requirements.

5. StreamChat

Stream specialises in providing chat and activity feed APIs for developers to easily add real-time chat and feed functionality to their applications. In addition to chat, Stream also offers activity feed functionality, enabling developers to create social feeds, news feeds, or any type of activity stream within their apps. 

They provide comprehensive documents, code samples, and support resources to help developers effectively integrate the chat SDK into their applications. StreamChat is currently testing and refining audio and video calling features as they are in the beta phase of development. 

Additional reading:

Streamchat's limitations and how it compares with other alternate options

6. Twilio

Twilio is a cloud communications platform that offers a wide range of communication services, and one of its offerings is the Twilio Chat SDK.

Twilio is often categorised as a cPaaS provider, which means it offers a suite of communication-related APIs and tools that developers can use to build their own communication solutions. This includes not only chat but also voice, video, and SMS capabilities. One advantage of using Twilio's Chat SDK within the Twilio ecosystem is the ability to easily integrate it with other Twilio services, such as voice and video calling, SMS messaging, and more.

Aarathy Sundaresan

Content Marketer , CometChat

Aarathy is a B2B SaaS Content Marketer at CometChat, excited about the convergence of technology and writing. Aarathy is eager to explore and harness the power of tech-driven storytelling to create compelling narratives that captivate readers. Outside of her professional pursuits, she enjoys the art of dance, finding joy and personal fulfillment.