Qubit Messenger

Qubit is a minimalist post-quantum messenger. Unlike most messengers, Qubit uses only symmetric cryptography — no RSA, no Diffie-Hellman, no elliptic curves. None of the schemes that quantum computers threaten.

How it works: • Meet your contact in person. Agree on a shared key. • Enter that key on both phones once. It never leaves the device. • Every message is encrypted with AES-256-GCM on your iPhone before it leaves. The server only stores ciphertext.

What we don't do: • No phone number, email, or address book required. • No group chats, no attachments, no reactions. By design. Open the channel only with someone you've actually met. That's the entire trust model. Simple. Auditable. Future-proof.

Terms of use: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/