Comparison
RVNT vs Briar
RVNT: A peer-to-peer, post-quantum, end-to-end-encrypted messenger with no phone number and no servers. · Briar: Briar is a free, open-source peer-to-peer messenger that syncs end-to-end-encrypted messages directly between devices over Tor, Wi-Fi, or Bluetooth with no servers and no phone number or email.
Bottom line: If you need something you can trust today against an active, network-level adversary, Briar wins on the things that matter most: a real (if aging) Cure53 audit, years of field use, sustained funding, and the best offline-without-internet resilience available. Choose RVNT only if its specific advantages are decisive for you — post-quantum encryption, an on-device duress PIN, iOS support, and high-volume file transfer — and you accept that it is still pre-release and not independently audited.
Briar and RVNT share an unusually pure threat model: both are fully peer-to-peer with no central servers for message content, both refuse phone numbers and emails, both use local identifiers rather than a global directory, both default to routing over Tor, and both are open source with no telemetry. The differences are about maturity versus modern cryptography. Briar is the proven, audited, grant-funded incumbent with a years-long track record in hostile environments and a unique offline mesh story (Bluetooth/Wi-Fi/removable media, plus an optional self-hosted Mailbox). RVNT is a pre-release project that layers post-quantum key exchange (X25519 + ML-KEM-768) on top of the Signal-style Double Ratchet, adds an on-device duress PIN, runs on iOS as well as desktop, and is built specifically as a bulletproof large-file-sharing network — but it is unaudited, unfunded, and unproven.
The facts, side by side
| RVNT | Briar | |
|---|---|---|
| End-to-end encrypted by default | Yes | Yes |
| Encryption protocol | Hybrid post-quantum X3DH (X25519 + ML-KEM-768) + Double Ratchet, AES-256-GCM | Bramble protocol suite (BTP/BHP) — XSalsa20-Poly1305 AEAD, keyed BLAKE2b KDF Briar does not use Signal's Double Ratchet for transport. The Bramble Transport Protocol (BTP) uses XSalsa20/Poly1305 as its authenticated cipher (KEY_LEN 32, NONCE_LEN 24, AUTH_LEN 16) with keyed BLAKE2b (PRF_LEN 32) as the PRF/KDF, and rotates per-time-period transport keys derived one-way from a root key (KDF(...,"...transport/ROTATE", period)), giving forward secrecy suited to delay-tolerant networks. Verified against the Bramble Transport Protocol spec. |
| Post-quantum key exchange | Yes | No Briar uses classical elliptic-curve/symmetric crypto only. There is no ML-KEM / post-quantum key exchange. (RVNT, by contrast, layers ML-KEM-768 with X25519.) |
| Requires a phone number | No | No No SIM, phone number, email, or messenger ID is required to register — a deliberate design goal. Confirmed in Briar's Quick Start guide (account = nickname + password only). |
| Requires an email address | No | No |
| How you’re identified | Local Ed25519 keypair, username claimed by proof-of-work | Local nickname + password; contacts added by in-person QR scan or by exchanging a one-time briar:// link ("add contact at a distance"). No global account or directory. There is no central account or username directory, so you cannot be found or messaged by strangers; both sides must exchange a QR code in person or a one-time briar:// link (valid 48 hours) out-of-band. This adds friction but blocks spam and enumeration. |
| Architecture | peer-to-peer | peer-to-peer Truly serverless P2P: there is no Briar-operated infrastructure that relays or stores messages. Devices sync directly (Tor, Wi-Fi, Bluetooth, or removable media). Because peers must be reachable at the same time, Briar offers an OPTIONAL, self-hosted 'Briar Mailbox' (a companion Android app the user runs on a spare always-on device, reached over Tor) that buffers encrypted messages for offline delivery — store-and-forward without any third-party server. |
| Metadata protection | Sealed sender + Tor by default + mixnet (cover traffic, fixed-size padding) | Strong — no servers store metadata; internet sync runs over Tor v3 hidden services, hiding IP/relationship metadata. Contact graph and message content live only on-device. |
| Routes over Tor by default | Yes | Yes Online sync runs over the Tor network by default via v3 onion services; Briar can also sync directly over Wi-Fi or Bluetooth when there is no internet, in which case Tor is not involved. |
| Open-source client | Yes | Yes |
| Independently audited | No RVNT is pre-release and has not yet completed a formal third-party security audit — the code is open source so it can be reviewed, but treat it as not-yet-audited. | Partial Independently audited by Cure53 in March 2017 (BRP-01); all issues found were fixed before the beta release, and the reviewers called the code quality 'rather exceptional' and concluded Briar 'can be recommended for use'. In 2023 ETH Zürich researchers (Yuanming Song & Kenny Paterson) disclosed three issues, including a non-forward-secret Bramble Handshake Protocol (CVE-2023-33982, CVSS 5.9, fixed in 1.5.3 on 2023-05-24); the team then requested a fresh independent protocol-stack audit. Marked 'partial' because the published audit is ~9 years old and predates the current desktop client. |
| Jurisdiction / who can be subpoenaed | Peer-to-peer (no central operator to subpoena) There is no company-run server that relays or stores message content, so there is no inbox in a data center to subpoena. A small bootstrap server only holds public prekeys + peer-discovery data. | Project led from the UK; non-commercial, funded via grants (Open Technology Fund, NLnet/NGI Zero, and others). No corporate data-controller. |
| On-device duress / panic defenses | Yes | No No duress/decoy PIN or fake-vault feature. There is a single password protecting an encrypted on-device database; entering a wrong password simply fails to unlock. (RVNT ships an on-device duress PIN.) |
| Max attachment size | No limit on a direct link (P2P streaming) No size limit on a direct peer-to-peer connection (segmented streaming with resume-on-disconnect). Transfers that fall back to a relay are currently capped at 256 MB until resumable relay ships. | Images and small files supported on Android; no published hard size limit. No general large-file transfer. Briar is designed for resilient text messaging, forums, blogs and private groups; it is not a large-file-transfer tool. Image attachments are supported on Android; the desktop client's attachment support lags the Android app. |
| Collects telemetry / analytics | No | No No analytics/telemetry SDKs; the app is fully open source (GPL-3.0 Android, AGPL desktop) with no Briar servers to report to. The F-Droid build contains no proprietary trackers. |
The verdict
If you need something you can trust today against an active, network-level adversary, Briar wins on the things that matter most: a real (if aging) Cure53 audit, years of field use, sustained funding, and the best offline-without-internet resilience available. Choose RVNT only if its specific advantages are decisive for you — post-quantum encryption, an on-device duress PIN, iOS support, and high-volume file transfer — and you accept that it is still pre-release and not independently audited. For most high-risk users right now, Briar is the safer default; RVNT is the more forward-looking design that still has to earn the same trust.
Frequently asked questions
Does Briar need a phone number or email?
No. You create a local account with just a nickname and password — no SIM, phone number, email, or messenger ID is required. Because there is no central directory, strangers cannot find or message you; you add contacts by scanning each other's QR code in person or exchanging a one-time briar:// link (valid for about 48 hours).
Does Briar work without the internet?
Yes. When online it syncs over the Tor network to hide your IP and relationships; when the internet is down it can sync directly between nearby devices over Bluetooth or Wi-Fi, and messages can even be carried on removable media. For contacts who are online at different times, an optional self-hosted Briar Mailbox can buffer encrypted messages until you reconnect. This delay-tolerant design is what makes it useful during blackouts and censorship.
Is Briar's encryption audited and is it post-quantum?
Briar's messages are end-to-end encrypted with the Bramble protocol suite (XSalsa20-Poly1305 with keyed BLAKE2b key derivation and rotating, forward-secret transport keys). Cure53 audited it in 2017 and recommended it for use; ETH Zürich researchers later found and helped fix a handshake weakness (CVE-2023-33982, patched in 1.5.3). The cryptography is classical, not post-quantum — there is no ML-KEM.
Can I use Briar on iPhone?
No. Briar runs on Android and, in beta, on desktop (Windows, macOS, Linux). The developers have stated they have no plans for an iOS app, largely because of iOS background-execution, Bluetooth/Wi-Fi, and Tor restrictions that conflict with Briar's always-syncing peer-to-peer model.
Comparisons here are kept honest and dated — we name where the other app wins. RVNT is the post-quantum, peer-to-peer option with no phone number and no servers.