Is Signal safe to use?
Yes — Signal is widely considered the safest mainstream messenger and is the default recommendation of most security and privacy experts. Everything is end-to-end encrypted by default using the open, independently analyzed Signal Protocol, which Signal has extended with post-quantum cryptography (PQXDH in 2023 and the Sparse Post-Quantum Ratchet in October 2025). It is open source, run by a U.S. nonprofit funded by donations rather than ads, collects essentially no metadata, and has proven in response to real grand-jury subpoenas that it can only produce an account's creation date and last-connection time. The main caveats are that it requires a phone number to register and runs on central servers, so connection-level metadata (and the fact that you use Signal) is more exposed than in a serverless design.
Where Signal is strongest: Maturity and scrutiny: Signal's protocol has over a decade of real-world deployment and landmark academic cryptographic analysis (IEEE EuroS&P 2017) plus formal verification of PQXDH. RVNT is pre-release and has had NO independent audit yet.. On metadata, Signal relies on Sealed sender hides the sender from Signal's servers; private contact discovery and encrypted profiles/groups minimize what the server can see, but a central server still routes all traffic, and it is partly audited. See the full Signal vs RVNT comparison for the side-by-side.