Atmosphere — private messenger for Android: chats, groups & calls without a phone number
Free · No ads · E2EE

Chat privately — no phone or email required

Atmosphere is a username-based private messenger (no forced phone number or email) with personal and group chats, voice and video calls, end-to-end encrypted messages, and no storage of conversations on our servers.

  • End-to-end encrypted chats
  • Groups with full chat and calling
  • No mandatory phone number or email
  • Minimal metadata on the server
Download for Android Learn more
Simplicity, privacy, and reliability — messaging with Atmosphere.
Register with username and password — no phone number or email required.
Free to use with no ads in your chats.
Personal and group chats, attachments, voice and video calls in one app.
Customize the chat experience — backgrounds, intensity, and messaging options.

Why Atmosphere

End-to-end encryption

Messages are protected on device; the server relays ciphertext only. Built with modern cryptographic practices in mind.

Simplicity & lightness

The UI and features are built around conversation — no clutter, no heavy extras for their own sake, nothing that pulls you away from chat. The app stays light and predictable so communication stays front and centre.

No ads or paywalls

We aim to keep core chat free without monetizing your conversation stream.

Username, not phone or email

Sign up with a unique login and password — no account tie-in to a phone number or email address. Use your seed phrase to recover keys on a new device.

Groups: chat & calls

Full-fledged group conversations with messaging and attachments, plus voice and video calls — alongside direct chats in one consistent experience.

History stays on your device

Chats, contacts, and encryption keys are stored locally; we don’t offer a full cloud copy of your conversations on our servers — the model keeps control with you.

Privacy controls for how people reach you

Settings help limit who can DM you and start calls, manage profile visibility, and use block lists — so messaging follows your rules.

About the messenger

Atmosphere is built as an alternative to messengers that tie accounts to phone numbers or email and collect excessive data. We focus on privacy, keeping conversations only on participants' devices, and simple, approachable chat — including groups with the same privacy-minded approach as direct messages.

Cryptography and key exchange follow ideas close to the Signal ecosystem: forward secrecy, modern primitives, and a clear picture of what the server can see.

We aim to request as few device permissions as possible, send data only in encrypted form, and store on the server only the minimum needed to establish connections.

FAQ

How do I register?
Install the app, pick a username and password. After sign-up you will see a 12-word seed phrase — store it safely; you need it to recover keys on another device.
Are there group chats and calls?
Yes — you can use groups with full chat (messages and attachments) and join voice and video calls, alongside direct conversations. This is available in the current Android app.
Why no phone number or email?
Your handle is your username. That reduces SIM- and inbox-centric identity, keeps server-side data smaller, and avoids requiring a phone or email to sign in.
How secure are messages?
Chats use E2EE; the server does not see plaintext content. Protect your device, app PIN/biometrics, and seed phrase.
How do I recover my account?
On a new device use login, password, and the seed phrase in the recovery flow. Without the phrase keys cannot be restored — by design.
Is history synced across devices?
The model favours local message storage on each device. See project docs as multi-device features evolve.
What does Atmosphere cost?
The app is free. We do not charge for core chat or inject ads into messages.
What does alpha mean?
APIs, UI, and storage policies may still change. Follow app updates and keep a backup of your seed phrase.
What does the server see?
The server handles delivery signals, username accounts, and technical metadata needed to run the network. E2EE message bodies are not decrypted on the server.

Roadmap

Done

Server & Android

Server infrastructure and the Android client: direct and group chats, media, calls, privacy settings — ongoing improvements and stabilization.

Released

Planned

iOS app

Feature parity targets: sign-up, E2EE chats, contacts.

Planned

Planned

Windows / macOS desktop

Native or cross-platform clients for keyboard and large screens.

Planned

Support the project

Atmosphere is conceived, built, and maintained by one person. If it resonates with you, you can support it financially.

Ways to support

Contact the team

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