How this compares
Six messengers, side by side. Two of them, Flamenet Messenger and SimpleX, run on servers you can host yourself and ask for no phone number. What only Flamenet Messenger does here: your address comes from your passphrase rather than the server, so a relay shutting down costs you a mailbox, not your name. The rest is laid out plainly and sourced from each project's own documentation, so you can check every line of it.
| Flamenet | Signal | Telegram | Apple Messages | SimpleX | ||
|---|---|---|---|---|---|---|
| Nobody in between can read it | Yes Every conversation. There is no plain mode to switch to. |
Yes | No Only in Secret Chats, which are one-to-one and have to be started deliberately. |
Yes Between Apple devices, and with Android since iOS 26.5, but only for the newer kind of text message, not the old kind. |
Yes Personal messages and calls, by default. |
Yes Chats and groups. Public channels are the exception: the relays that carry them can read them, by design. |
| Works without a phone number | Yes A username. A server that keeps its own accounts also asks for an email address. |
Partly New accounts on Android, through the paid registration Signal documents as "Phone Numberless Registration". An account that already has a number cannot drop it, and usernames hide a number from other people but not from Signal. |
No | Partly An Apple ID, reachable by phone number or email. |
No A phone number is required to register. |
Yes It asks for no phone number or username, and does not even assign a random number. You connect by passing a link or QR code. Optional public names for channels and contact addresses are in testing. |
| You can run the server yourself | Yes Two containers and a config file. |
No | No | No | No | Yes A message server and a file server, each installed with a script or Docker. The app lets you switch off the preset servers. |
| Message someone on a different server | Android & iPhone beta Like email. Both sides need it; servers choose who they talk to. |
No Deliberately. Letting servers talk to each other means more companies learn who is talking to whom, which Signal has chosen not to do. |
No | No | Partly In Europe only, with apps that have signed up to connect, because EU law requires it. You have to opt in. |
Yes Each person picks the servers they receive on, and anyone can still write to them. There are no accounts on the servers. |
| You keep your name if you move servers | Android & iPhone beta Your address comes from your passphrase, not from the server. |
No Your account lives on Signal's servers. |
No | No | No | Partly There is no name to lose. Moving means switching each contact to a new server by hand, and only while the old one still works. |
| Messages can wait for you in more than one place | Android & iPhone beta Keep a mailbox on two servers, added before you need it. |
No | No | No | No | No Planned. For now each contact's messages wait on one server. Public channels already use several relays. |
| Anyone can read the code | Apps and server MIT licence: both apps, the server, the encryption code. |
Apps and server Under licences that require anyone who changes it and runs it for others to publish their changes. |
Apps only The server side is closed. |
No | No The apps and servers are closed. Meta publishes some parts, such as the library behind its key checking. |
Apps and server AGPL licence for the apps and both kinds of server, which requires anyone who changes it and runs it for others to publish their changes. |
| Safe from the computers that are coming, when a conversation starts | Android & iPhone beta Against recording now and decrypting later. Both sides need it. |
Yes Yes, at the start of a conversation. |
No | Yes Yes. Apple has done this longest. |
Not stated Meta's published post-quantum work protects the connection to its servers, not the messages themselves. |
Yes One-to-one chats, on by default since April 2024. Groups do not have it yet. |
| And every message after that | Android & iPhone beta Fresh keys every message, not just at the start. Both sides need it. |
Yes Signal added this in October 2025 and is rolling it out gradually. It works alongside what they already had rather than replacing it. |
No | Yes Yes. Apple has done this longest. |
Not stated | Yes A new post-quantum key exchange each time the conversation changes direction, since 2024. One-to-one chats only. |
| Your app checks your contact is really them | iPhone Automatic, and a server that goes quiet counts as caught. Android does not check the list yet; safety numbers work on both. |
Yes Automatic Key Verification, opt-in, since August 2026. |
No | Yes Contact Key Verification, opt-in. |
Yes Automatically, through key transparency, since 2023. |
By hand You compare a security code with your contact, or scan theirs. Nothing checks it for you. |
| Your history survives losing the phone | Partly An export sealed with a passphrase you choose, saved wherever you like. Nothing continuous, and the server keeps none of it. |
Yes Encrypted backups, added in 2026, with a recovery key only you hold. |
Yes Cloud chats live on Telegram's servers, which is also why somebody in between can read them. |
Yes Through iCloud, encrypted end to end only if Advanced Data Protection is turned on. |
Yes Backups to Google Drive or iCloud, encrypted end to end only if you turn that on. |
Partly Only if you exported a copy by hand first, locked with your passphrase. Moving to a new phone needs the old one. Backups on the server are planned. |
| Checked by outsiders | Planned The scope is written and public, and an audit grant has been applied for. |
Yes | Partly Its protocol has been examined externally, with mixed findings. |
Yes Apple’s design was examined by academics outside the company. |
Partly Two parts were publicly reviewed by NCC Group: the encrypted backups in 2021 and the key directory in 2023. The app itself is closed. |
Yes Trail of Bits reviewed the code in 2022 and the protocol design in 2024. A 2026 code review is announced but not yet published. |
| You can install it today | Android yes Android now. iPhone is in beta, not yet on the App Store. |
Yes | Yes | Yes | Yes | Yes iPhone, Android, Windows, Mac and Linux. No web version. |
| People already using it | Early days New. The people arriving now shape what it becomes. |
Many millions | Hundreds of millions | Built into every iPhone | More than two billion | About 480,000 a month SimpleX's own figure from August 2026, with more than 3 million downloads. With no accounts to count, it does not say how it arrived at it. |
| What pays for it | Donations | Donations and grants, to a non-profit | Ads and subscriptions | Selling the hardware it runs on | Meta, including ads in Status and Channels | Investors and donations, to a company; since 2026 also paid supporter badges and shares sold to the public |
One design difference worth naming: sent, never hosted
On every mainstream platform, a story or a profile photo is hosted: the server holds one copy and decides, per viewer, who is shown it. Your audience setting is a promise the operator enforces, and could stop enforcing, or be compelled to.
Here a story is sent. When you post one, your device encrypts it separately to each person in the audience you chose and delivers it like any other message. Someone outside the audience is not "denied access", there is nothing to deny them access to. No copy exists on the server that a policy, a bug, or a subpoena could ever widen the audience of. The per-story audience picker in the composer is that property made visible: the choice happens on your device, before anything leaves it, and it is enforced by who receives the bytes rather than by who is shown them. The honest cost is the same one it always is: an audience decided at send time cannot be widened later without sending again.
Reading the table fairly
Rows are easy to count and harder to weigh. Apple's key transparency has run for years across a billion devices; ours is new, and scale is a security property of its own. Trust the table, not the tone of it.
All six are serious pieces of engineering, and on post-quantum we are not ahead of anyone: Apple and Signal both carry it through the ongoing conversation, Signal since October 2025, and SimpleX has done the same in one-to-one chats since 2024. This page scored that row wrong once, in our own favour, which is the kind of mistake the note below asks you to report. It also used to say that nothing else here runs on a server you can host yourself with no phone number attached. SimpleX does both, and goes further than we do on hiding who talks to whom: it gives you no name or number at all, and is built so a server cannot easily tell which conversations belong to the same person. What Flamenet Messenger offers instead is a username people can find you by and a buddy list that shows who is online, the way AIM did. The cost is that the server knows account names and which of your devices are online, and for now it also keeps your contact list. If you would rather no server could tell who you are, SimpleX is the better choice.
Where these facts come from
Everything above is drawn from each project's own published documentation and from public security research, checked in September and October 2026. These are given as references rather than links, because this site deliberately doesn't send you anywhere else:
- Signal, Signal Support, "Phone Number Privacy and Usernames" and "Phone Numberless Registration for Android"; Signal blog, "Keep your phone number private with Signal usernames"; the PQXDH specification; Signal blog, "Introducing Automatic Key Verification" (August 2026).
- Telegram, Telegram Core API, "End-to-End Encryption, Secret Chats", which documents that cloud chats are client–server encrypted and that Secret Chats are opt-in and one-to-one.
- Apple, Apple Security Research, "iMessage with PQ3"; Apple Support, "iCloud data security overview"; the iOS 26.5 release notes covering encrypted RCS; Stebila, "Security analysis of the iMessage PQ3 protocol", and the USENIX Security 2025 formal analysis of PQ3.
- WhatsApp, WhatsApp Help Center, "About end-to-end encryption", "About end-to-end encrypted backup" and "About ads in WhatsApp Status and Channels"; the WhatsApp privacy page; Engineering at Meta, "Deploying key transparency at WhatsApp" and "Post-quantum readiness for TLS at Meta"; Meta, "Messaging Interoperability: WhatsApp enables third-party chats for users in Europe"; and NCC Group's public reports on WhatsApp's end-to-end encrypted backups (2021) and its Auditable Key Directory (2023).
- SimpleX, the README and LICENSE files of the simplex-chat and simplexmq repositories; SimpleX docs, "SimpleX Chat FAQ", "Hosting your own SMP Server", "Hosting your own XFTP Server", "Security Policy", and the user guide pages "Privacy & security", "Making connections" and "Managing your data"; the protocol documents "Post-quantum resistant augmented double ratchet algorithm" and "SimpleX Channels: stateful information delivery and management"; SimpleX blog posts on v5.6 and v5.7 (March and April 2024), its 2024 funding, the 2024 design review, channels (April 2026), public names (July 2026), equity crowdfunding (August 2026) and supporter badges (September 2026); and Trail of Bits, "SimpleX Chat Security Assessment" (2022) and "SimpleX Chat Design Review" (2024).
- Flamenet Messenger, the specification, the metadata page and the roadmap on this site.
The real names, if you want to go and check
Nothing in the table above uses these, on purpose: a heading you have to look up first has asked you to do our work. They are here because a reader who wants to verify a row needs the actual term to search for, and leaving them out entirely would be its own kind of unhelpful.
- Safe from the computers that are coming, the field calls this post-quantum cryptography. At the start of a conversation Signal calls theirs PQXDH, Apple’s is part of PQ3, and ours is a hybrid of X25519 and ML-KEM-768, and SimpleX pairs X448 with sntrup761, also called Streamlined NTRU Prime.
- And every message after that, the repeating part of a conversation’s encryption is called a ratchet. Signal’s post-quantum one is the Sparse Post-Quantum Ratchet, announced October 2025; ours is protocol v3; SimpleX’s is the post-quantum resistant augmented double ratchet (PQDR), added in version 5.6 in March 2024.
- Your app checks your contact is really them, key transparency, built on an append-only Merkle log. Signal calls its version Automatic Key Verification. SimpleX’s hand comparison is its security code.
- Anyone can read the code, ours is MIT; Signal’s apps and server are AGPL and GPL, and SimpleX’s apps and servers are AGPL version 3.
- Message someone on a different server, federation.
- Between Apple devices, and with Android, the newer kind of text message is RCS; the old kind is SMS.
- Works without a phone number, SimpleX describes itself as having no user identifiers; instead each conversation runs over its own one-way message queues. Its optional names are SimpleX public names, ending in .simplex.
- You keep your name if you move servers, SimpleX calls moving one contact to another server Change receiving address, also known as queue rotation.
- You can run the server yourself, SimpleX’s message server is an SMP server and its file server an XFTP server.