Privacy

Union connects your own machines to each other. Here is what it keeps to do that, and what it does not.

Last updated September 26, 2026.

What we keep

• Your account: your email address and the ways you sign in (a password, Apple, Google). Passwords are stored hashed by our sign-in provider; we never see them.
• Your devices: each device’s name, what kind of device it is, an identifier the app makes for it, and when it last connected — so your devices can be listed for you. You can rename or remove them.

What we don’t

• What is on your screens, the sound, what you type and click, your clipboard and the files you send all go between your own machines. None of it is stored on our servers.
• No advertising, no analytics, no tracking.

How your machines connect

• To find each other, your devices keep a connection to our signaling server. It passes on the short messages that set up a connection between two of your devices — never what the connection then carries.
• Over the internet, connections are encrypted end to end. When two machines cannot reach each other directly, the encrypted traffic goes through a relay server we run, which cannot read it.
• On your own local network, your machines can connect to each other directly.

Who helps us run it

• Supabase — accounts and the device list.
• Cloudflare — this website, the web app and the downloads.
• Sakura Internet (Japan) — the servers for signaling and the relay.
• Apple and Google — only if you choose to sign in with them.

On your devices

• The apps keep logs on the device to help work out problems. They are not sent anywhere unless you send them to us.
• The web app keeps an identifier for your browser and your settings in the browser’s storage.

Deleting your data

Delete your account from Union’s account settings or from the web app. Your account, its sign-in methods and its device list are deleted, and every device signed in with it loses access.

Contact

Questions about privacy: support@unionlink.app.