| Price from | $400/mo | $10/mo |
| Free plan | — | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | — | Yes |
| Linux | Yes | Yes |
| iOS | Yes | — |
| Android | Yes | — |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 3 | 2 |
| Spec score · Chat APIs | 8.2 (#7) | 8.4 (#4) |
| Deployment | ChatKitty is packaged as one Docker container backed by PostgreSQL and Redis-compatible Valkey on a standard Linux deployment. | Emitter can be deployed as a Docker container or built and run from source; the maker describes single-server and clustered deployment. |
| Messaging | The launch sprint supports one-to-one conversations, private groups, channels, membership, and message history. | Publishers send messages to channels, and subscribers receive copies in real time. |
| Product | ChatKitty provides a production-ready messaging core with open-source integrations for marketplace and community products. | Emitter is a real-time publish-subscribe messaging service for connecting online devices. |
| Security | Chat Functions run in a secure cloud environment and can implement custom authentication logic, including Firebase token verification. | The maker says Emitter supports per-channel authorization policies and SSL/TLS, encrypts network traffic, and does not inspect messages. |
| Support | The launch sprint includes production planning, release support, and 14 days of post-launch defect correction for the agreed scope. | The maker offers support contracts and directs questions to [email protected] and GitHub issues. |
