Kontalk vs SimpleX Chat
Kontalk
kontalk.orgSimpleX Chat
simplex.chatSide by side
| Figure | Kontalk | SimpleX Chat |
|---|---|---|
| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | Yes |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | — | Yes |
| iOS | — | Yes |
| Android | Yes | Yes |
| API | — | Yes |
| Self-hosted | — | Yes |
| Plans published | 1 | 2 |
| Spec score · Encrypted Messaging Apps | 7.2 (#34) | 8.4 (#3) |
| Spec score · Secure Messaging Apps | 7.3 (#31) | 8.5 (#5) |
| Encryption | The site says client-to-server and server-to-server channels are fully encrypted, and servers cannot decrypt end-to-end encrypted messages. | The network uses end-to-end encryption with continuous post-quantum key exchange for messages and metadata. |
| Open source | The site says all software used in the network, including both server and client software, is open source. | Alternative client applications based on SimpleX Chat code must publish modifications under the AGPLv3 license. |
| Support | The project links users to a help wiki and a community forum for discussion. | Users can contact the team through the in-app “Ask SimpleX team” contact or by emailing [email protected]. |
Plans
In their own words
SimpleX Chat
SimpleX Chat is a messaging application for the SimpleX platform, with apps for Android, iOS, Linux, macOS, and Windows. It supports encrypted text with Markdown and editing, media and file sharing, decentralized groups, voice messages, disappearing messages, and audio and video calls. The network does not assign profile identifiers such as phone numbers or usernames. Messages and metadata use end-to-end encryption with continuous post-quantum key exchange. Four servers participate in each chat so relay servers cannot see which IP addresses communicate. Profiles, contacts, and messages remain in a portable encrypted database on user devices; relay servers hold encrypted messages only until delivery. Users may operate their own servers and still reach people using preconfigured servers. Developers can build bots and integrations using protocol SDKs; the TypeScript SDK connects to the Chat CLI over a WebSocket API. A phone or tablet can link to the desktop app only when both devices share a local network. Disappearing messages and recipient-side deletion are not guaranteed when a recipient device is offline or modified. The free plan costs nothing.