IcyZip

IcyZip is a web service from a sole trader in Steyr, Austria, for exchanging text between two devices, for example between a smartphone and a computer. One device opens the website and shows a QR code, the second scans it and opens the link in its browser. Both browsers then share a live text field. Once both are connected, files can also be sent, up to 25 MiB in the first release, and both tabs must stay open for this. No account, app or email address is required, but the provider points out that anyone with the complete link can join the pairing.

According to the privacy policy, IcyZip runs on its own server infrastructure; the hosting provider and server location are not named. The service does not use a direct peer-to-peer connection but forwards the encrypted content between the paired browsers via a coordination service over WebSocket. The server sees metadata such as file names, sizes, timing and connection data, but no plaintext or file content. Pairing IDs are kept for up to 30 days, server logs for 14 days. IcyZip sets no cookies and loads no third-party analytics, advertising or tracking services.

Partly. The browser encryption module, including runnable security tests, is published under the Apache 2.0 licence in a self-hosted Git repository. According to the provider, the server software is proprietary and not part of the package. Encryption uses ECDH with P-256 via WebCrypto, HKDF-SHA-256 and 256-bit AES-GCM, and files are encrypted in chunks with a fresh nonce each. The pairing secret sits in the URL fragment and is therefore not transmitted to the server.