Keep Factually independent
Whether you agree or disagree with our analysis, these conversations matter for democracy. We don't take money from political groups - even a $5 donation helps us keep it that way.
What is Session Messenger and how does it differ from other secure messaging apps?
Executive summary
Session is a privacy-focused, open‑source messenger that began as a fork of Signal and now uses its own Session Protocol plus a decentralized onion‑routing network to remove phone numbers and reduce metadata exposure [1] [2] [3]. Compared with Signal, Session emphasizes anonymity and metadata resistance at the cost of smaller network effects, sometimes weaker call quality, and a more “underground” user base [3] [4] [5].
1. What Session is: an anonymity‑first, open‑source messenger
Session started as a fork of Signal and retained end‑to‑end encryption foundations while purposefully steering away from Signal’s centralized model; it’s run by the Session Technology Foundation and is fully open source, with code available on GitHub [1] [3]. The app lets you create accounts without providing a phone number, email, or other personal details—users can sign up with a username only—so Session is designed to give users an anonymous identifier rather than a phone‑linked identity [3] [2].
2. How Session’s architecture differs: decentralized routing and Session Protocol
Session built a different stack on Signal’s heritage: it uses the Session Protocol (inspired by Signal but implemented with different libraries such as Libsodium) layered over a distributed onion‑routing network and decentralized nodes to forward messages, aiming to limit metadata collection and avoid single‑server vulnerabilities [1] [6] [2]. This design replaces Signal’s centralized servers with a network of nodes (and, historically, reliance on the Oxen blockchain and staking models has been part of the project’s infrastructure discussions) to create stronger anonymity and reduce metadata leaks [2].
3. Security commonalities: end‑to‑end encryption and open code
Both Signal and Session provide end‑to‑end encryption; Session inherited core security concepts from Signal’s codebase and explicitly uses E2EE for all conversations [1] [3]. Session and Signal are open source, which allows independent review and builds trust in the cryptographic foundations [1] [3].
4. Tradeoffs: anonymity vs. convenience and features
Session prioritizes anonymity and metadata resistance, but that comes with practical tradeoffs. Reviewers note inconsistent call quality and fewer community and user‑experience features compared with Signal, making Session less convenient for broad friend‑and‑family adoption [3]. Analysts characterize Session as “underground” and better suited to users whose threat model values anonymity above mainstream usability; Signal is framed as the smarter choice for most people because of reliability, usability, and broader adoption [4] [5] [3].
5. Metadata and threat models: why Session exists
Critics of centralized systems argued Signal’s phone‑number requirement and centralized servers can expose metadata even if messages are encrypted; Session was developed to address those concerns by removing phone numbers and decentralizing routing to minimize metadata trails [2] [6]. Different users have different threat models: for everyday private messaging, Signal’s balance of usability and security often suffices; for “high‑risk anonymity” (activists, journalists in repressive contexts, or users wanting minimal metadata), Session is presented as the stronger option [4].
6. Adoption and network effects: the practical limit
Multiple writeups warn that Session’s anonymity focus reduces network effects: you’ll likely need to recruit contacts to join, and communities require invite links or QR codes, which can limit discoverability and mass adoption compared with Signal [3] [4]. Reviewers also put Session behind Signal in mainstream appeal and note its smaller user base and more specialized audience [3] [5].
7. What to consider when choosing between them
Choose Session if your priority is minimizing metadata, avoiding phone‑number identifiers, and maximizing anonymity even if you accept potential call quality issues and fewer social features [2] [3]. Choose Signal if you want a widely adopted, user‑friendly, strongly encrypted messenger with reliable call quality and easier onboarding for contacts, recognizing Signal uses phone numbers for account creation and is centralized [3] [4].
Limitations: available sources in this bundle do not provide independent technical audits comparing Session Protocol versus Signal Protocol in exhaustive detail, nor do they give up‑to‑the‑minute user counts; those specifics are not found in current reporting (not found in current reporting).