While the audit, “ A Formal Security Analysis of the Signal Messaging Protocol,” (.PDF) looked at the protocol’s code it did not review any third-party implementations of the protocol.

The Signal Foundation, maker of the Signal Protocol that encrypts messages sent by more than a billion people, has rolled out an update designed to prepare for a very real prospect that’s never ...

The Signal messaging app uses end-to-end encryption so that your texts, calls, videos, files, and location remain private. Here's how to use it.

Open source: Signal is fully open source, with its app and protocol code publicly available for review and improvement. This transparency builds trust in its security mechanisms.

This strongly suggests that the company plans to use the same E2E encryption used by secure messaging app Signal. Twitter will adopt the Signal Protocol for Encrypted DMs.