Nothing is transmitted anywhere except as light. There is no account, no pairing, no analytics, and no network path between the devices — the site works with the network off after the first visit.
The channel is not confidential. Whatever is on the sending screen is readable by any camera pointed at it. The property Decimen gives you is no network, not encryption. Don't stream secrets in a room you don't trust.
Integrity is checked. Every received file is verified against its SHA-256 before being offered; a corrupted stream fails loudly rather than handing over damaged bytes.
- Text snippets: nothing. Shown with a Copy button, gone when the tab closes.
- Files you save go wherever your browser puts downloads.
- Received media (video/audio, so the in-page player can seek) is staged in the browser's Cache API and would otherwise linger until the next transfer overwrites it. The Clear Decimen cache button next to Receive another file deletes it on the spot — use it before handing the phone to someone.
- The service worker's offline cache holds the app itself, never transferred content.