Keybase vs SimpleX Chat

Keybase is a free messaging and file-sharing product for Android, iOS, Linux, macOS, web and Windows. It uses public-key cryptography for private chats and says messages and files are end-to-end encrypted so only users and intended recipients can read them. Private keys stay on users’ devices rather than Keybase’s servers. Users can set timers on sensitive messages in one-to-one chats and team, group and community channels. Teams bring together private chats with multiple channels, file sharing and collaboration on Git. Team chats, files and Git are end-to-end encrypted, and team keys change when someone is removed or revokes a device. Teams and subteams can store up to 100 GB of documents, photos and videos; personal Git repositories have a combined 100 GB limit, and each team gets 100 GB for Git. Keybase also supports public communities and identity proofs involving integrated social networks. The download page describes it as open source, and business admin controls are available. For client bugs, Keybase directs users to run `keybase log send` in a terminal and follow the instructions.

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.