Deep Technical Comparison: CometChat vs SendBird

CometChat is primarily offered as a SaaS platform and does not provide an official self-hosted version. All backend infrastructure and data storage are managed by CometChat’s cloud services. Teams requiring full self-hosting for compliance or data control purposes will need to consider alternative solutions or contact CometChat for enterprise options that might offer more control.

CometChat supports offline messaging by queuing messages on the server when recipients are offline and delivering them once they reconnect. The SDK provides local caching to ensure messages are available in the app even without a live connection, but full synchronization depends on the client reconnecting to the CometChat cloud backend. There is no built-in peer-to-peer offline mode.

Chat data stored in CometChat is owned by the customer using the service. CometChat provides APIs and dashboard tools to export chat histories and user data in standard formats. However, exporting large datasets may require use of their premium plans or contacting support for bulk export assistance. Data retention policies are configurable within plan limits.

CometChat enforces API rate limits based on the subscription tier to ensure service stability. Free and lower-tier plans have stricter limits on message throughput and concurrent connections, which can impact high-scale applications. The SDK supports all core messaging features, but some advanced capabilities like message translation or moderation require higher-tier plans. Detailed API limits are documented in their developer portal.

CometChat does not provide an automated migration tool, so teams typically export chat data from their existing platform and import it into CometChat using their REST APIs or SDKs. This process requires custom scripting to map user IDs, message formats, and metadata. Planning for downtime and data consistency is critical, and CometChat support can assist with best practices during migration.

SendBird is a fully managed platform and does not offer a self-hosted deployment option. All chat, voice, and video services run on SendBird's cloud infrastructure, so you cannot host the backend yourself. This simplifies scaling and maintenance but means you rely on SendBird's servers and compliance.

SendBird SDKs provide offline message caching on the client side to allow users to view recent chat history without a network connection. However, sending messages requires connectivity, and queued messages are sent once the device is back online. There is no fully offline mode where messages can be composed and stored indefinitely without syncing.

Data sent through SendBird is stored on their managed servers, but you retain ownership of your chat content. SendBird provides APIs to export message history and user data, enabling you to back up or migrate data. However, exporting large volumes may require coordination with SendBird support due to rate limits and data privacy policies.

SendBird enforces rate limits on API calls to ensure platform stability. Typical limits include a maximum number of requests per second per API key and restrictions on message send rates to prevent spam. These limits vary by plan tier, and exceeding them results in HTTP 429 errors. It's important to implement exponential backoff and batching where possible.

Migrating to SendBird requires exporting your existing chat data in a compatible format and then using SendBird's import APIs or SDKs to ingest that data. The process can be complex depending on the source platform's data schema and volume. SendBird provides some migration guides and support, but substantial custom scripting is often needed for full data fidelity.