Duet — Offline File Transfer

Move files, Wi-Fi, contacts and 2FA between phones — encrypted, over QR or your local network. No account, no ads, no tracking. It just works.

Duet sends what matters from one phone to another — and gets out of your way.

Pick a file, a contact, a Wi-Fi password, a 2FA setup code, or any text. The sender shows a QR code; the receiver scans it. For larger files, the two phones connect directly over your local network. Everything is end-to-end encrypted, and nothing ever touches a server.

No account. No sign-up. No ads. No tracking. No cloud.

WHY DUET • Reliable by design — built to finish the transfer, every time. • Truly private — your data goes phone-to-phone, never through us. We can't see it because it never reaches us. • Zero clutter — no ads, no upsells, no “create an account” wall.

WHAT YOU CAN SEND • Files of any kind — documents, photos, videos, archives. Streamed directly, so size isn't a problem. • Wi-Fi credentials — share your network without reading the password aloud. • Contacts — send a contact card that drops straight into the other phone. • 2FA / authenticator setup codes — move your TOTP seeds to a new phone. • Plain text and links.

HOW IT WORKS • Small items travel in a single QR code — scan and done, no network needed. • Larger items use animated QR or a direct local-network link between the two phones. Your data stays on your local network; it never goes to the cloud. • Every transfer is encrypted end-to-end. For the local-network mode, both phones show a quick visual match-check first, so you know there's no one in the middle.

PRIVACY YOU CAN VERIFY • Data Not Collected. No analytics SDKs, no ad SDKs, no trackers. • No internet connection is used to move your data. • Transfer contents are never written to permanent storage.

Duet is free, and it stays free. No subscriptions, no “pro” paywall on the core transfer.