SimpleX Chat vs WhatsApp vs Telegram: What "No Phone Number, No Username" Actually Means

Every messaging app you have ever used needs a way to know who you are. WhatsApp asks for your phone number. Telegram asks for a phone number too, and optionally a username that anyone can search. SimpleX Chat is the first messenger that asks for neither: no phone number, no username, no email, not even a random user ID behind the scenes.

This post explains what SimpleX Chat is, how it differs from WhatsApp and Telegram for day-to-day users, and what you actually do differently when nobody has an identifier.

The short version

• SimpleX Chat is an open source messenger with no user identifiers at all. It does not use phone numbers, usernames, or even random user IDs to identify people.
• You connect by exchanging one-time invitation links or QR codes, not phone numbers or usernames. Connections have to be created out-of-band, in person or through another channel.
• WhatsApp encrypts message content by default, but collects rich metadata tied to your phone number: who you talk to, when, how often, and from where.
• Telegram only encrypts chats end to end if you manually start a Secret Chat. Normal cloud chats can be read by Telegram's servers.
• SimpleX protects both content and metadata, and your profile, contacts and history live only on your device.
• The trade-offs are real: nobody can find you by name or number, backups are your job, and the network is much smaller.

What SimpleX Chat actually is

SimpleX Chat is an open source app for Android, iOS, Windows, macOS and Linux. It looks like a normal chat app: profiles, one-to-one chats, groups, files, voice messages, and audio and video calls. What is different is the foundation.

The project's own documentation is blunt about it: unlike any other messaging platform, SimpleX has no identifiers assigned to users. It does not use phone numbers, domain-based addresses, usernames, public keys, or even random numbers to identify people. The developers say they do not even know how many people use it.

Why does that matter for a normal user? Because every identifier is a hook. A phone number ties your account to your real-world identity, your carrier, and your address book. A username is a searchable handle that anyone can find and message. SimpleX removes the hook entirely. There is nothing to look up, nothing to link, nothing to search, which is exactly why it is also strong against spam: nobody can contact you unless you hand them a connection on purpose.

How you connect with people on SimpleX

The first thing to unlearn is "add by phone number". With SimpleX you exchange a one-time link or a QR code through another channel (in person, by email, in a different chat app), and the connection is created. Walk through it once and it takes about a minute:

1. Download SimpleX Chat from simplex.chat, the App Store, the Play Store, or F-Droid.
2. Tap Create and type a display name. That profile is stored only on your device, not on any server.
3. Pick a notifications mode. Read the explanation before choosing: on iOS this is a privacy versus convenience trade-off, and on Android it is a battery and delay trade-off.
4. To message a friend, tap the new chat button and create a one-time invitation link, or show the QR code. Share that specific link with that specific person.
5. Your friend taps "Connect via link / QR code" in the app, scans or pastes, and you are connected. No phone number changed hands.
6. If you want something more permanent, create a SimpleX contact address. It can be reused many times, which makes it useful in an email signature or on a profile page. You accept or reject each request, and you can change or delete the address without losing any connections.

Three extra details are worth knowing. Incognito mode creates a separate local profile so a new contact never sees your main display name. You can verify a connection by comparing a security code out-of-band, the same way you would compare fingerprints in any other messenger. And groups are built from per-member connections, with secret groups for invites that cannot be forwarded.

The three identifiers: phone number, username, nothing

The identifier is the whole story, so here is the direct comparison:

Privacy and metadata: what each company can actually see

Here is the distinction that most "end-to-end encrypted" messaging arguments miss: encryption protects content, privacy is about everything around the content. Who you talk to, how often, from where, on which devices. That is metadata, and the three apps sit in very different places on it.

WhatsApp: content protected, metadata rich

WhatsApp encrypts messages, calls and groups end to end by default using the Signal Protocol, so Meta cannot read the content in transit. But the account is tied to your phone number, and Meta collects a lot of metadata around it: who you message, when, how often, which groups you are in, device information, IP addresses, and the contacts in your address book. WhatsApp offers encrypted backups for chat history (with a key you control in most cases), but that protects the backup, not the metadata that Meta already holds. If your concern is "I do not want a company building a graph of my conversations", WhatsApp is not the app for that, no matter how strong its encryption is.

Telegram: default chats are not end to end encrypted

Telegram also requires a phone number. Your normal one-to-one and group chats are cloud chats: encrypted between your device and Telegram's servers, but Telegram holds the keys, stores the content in the cloud for multi-device sync, and can read it. End-to-end encryption exists only in Secret Chats, which you must start manually, which work only for one-to-one conversations, and which stay on the device where you started them. Telegram also retains metadata such as your phone number, IP address and message timestamps, and it has a long record of handing user data to authorities when legally required. If a chat is not marked as a secret chat, Telegram can see it.

SimpleX: no identifier, so much less to collect

SimpleX encrypts everything end to end by default, in two layers, with post-quantum key exchange, forward secrecy, and message padding. Because there is no user identifier, the relay servers (SimpleX calls them SMP servers) only see anonymous credentials for individual message queues.

A server cannot tell that queue A and queue B belong to the same person, and it cannot tell that they are talking to each other. Your profile, contacts and messages are stored only on your device; servers hold messages temporarily until they are delivered and store no accounts. The metadata that WhatsApp and Telegram collect as a matter of course is, in SimpleX's design, simply not there to collect.

What you give up (the honest trade-offs)

• No directory, on purpose. Nobody can find you by name or number, and you cannot find anyone else. Every connection starts with you sharing a link or a code through another channel. That is the feature and the friction at the same time.
• Backups are your job. With no account, there is no server-side restore to log into. SimpleX has a "Database passphrase and export" option in settings and an encrypted portable database you can move to another device, but you have to run it yourself, on a schedule.
• The network is smaller. WhatsApp has billions of users. SimpleX has a committed but much smaller community, so your family and colleagues have to install it and learn the link exchange before you can actually use it with them.
• Fewer cloud conveniences. There is no "log in on any device and your chats appear", because there is no account to log into. You link devices explicitly or move your database, which is more work and more private.
• iOS notifications involve a real trade-off. Instant push notifications share more metadata with the servers than the quieter alternative, so read the mode descriptions before you pick one.

Should you switch?

• Switch to SimpleX if: you want conversations that cannot be linked to an identifier, you care about metadata as much as content, you are willing to exchange links and back up your own database, and the people you talk to most are willing to install one more app.
• Keep WhatsApp or Telegram if: you need everyone you know to reach you by phone number, you rely on Telegram's cloud sync and channels, or the person at the other end will never install anything new.
• Try SimpleX alongside if: you are curious and want to feel the difference. There is no phone number to verify and no account to delete, so a low-stakes conversation with one friend is the whole cost of trying it.

Official sources

• SimpleX platform, motivation and comparison: https://simplex.chat/docs/simplex.html
• SimpleX quick start: https://simplex.chat/docs/guide/readme.html
• Making connections (invite links, QR codes, contact addresses): https://simplex.chat/docs/guide/making-connections.html
• SimpleX privacy and security guide: https://simplex.chat/docs/guide/privacy-security.html
• SimpleX downloads: https://simplex.chat/downloads/
• SimpleX releases on GitHub: https://github.com/simplex-chat/simplex-chat/releases
• WhatsApp security and encryption: https://www.whatsapp.com/security
• Telegram FAQ (encryption and cloud chats): https://telegram.org/faq
• ESET explainer on Telegram privacy: https://www.eset.com/blog/en/home-topics/privacy-and-identity-protection/telegram-privacy-explained/

Have you tried SimpleX, or are you still weighing it against WhatsApp and Telegram? What matters more to you: the metadata, the encryption, or getting your contacts to switch? Drop it in the comments.

Until next time, keep your systems thoughtful.