Matrix is a protocol for enabling real-time communication between different service providers.
Pro End-to-end encryption
Matrix features end-to-end encrypted chats which are syncronized accross all your devices.
E2E is [implemented in the matrix-js-sdk library and Riot.im client](http://matrix.org/git/olm/about, http://matrix.org/git/olm/tree/docs/megolm.rst, http://matrix.org/speculator/spec/drafts%252Fe2e/client_server/unstable.html#end-to-end-encryption).
Con Can only "redact" a posted message but neither "delete" nor "edit" it
The ability to edit a posted message is a powerful feature that has come to be expected since the rise of social media. Several other major chat platforms include this feature. Matrix.org's protocols enable you to "redact" a message (mark it as redacted whereas it is removed from view), but not truly delete or edit it. Deletion and editing are in the works, but in the meantime... CON.