Working

The phone app

The Synapse phone companion joins your sync as one more device. It shows your coding agents so you can answer them away from your desk, your hosts and vault, and on Android it opens SSH sessions too.

Pairing your phone

The phone joins by pairing with a code - it doesn't use your email. Your computer needs sync set up first: either Cloud sync and backup with your email, or Pair with a code instead → Start sync on this device if you'd rather not use an email. See Sync between devices.

1. On your computer, with the vault unlocked, open Cloud sync and backup, go to Devices and choose Add a device. A QR code and a pairing code appear. They expire after 10 minutes.
2. On the phone, open Synapse, give the phone a name (it's shown in your computer's device list) and choose Scan QR code. If the camera won't do, choose Enter the code instead and type the code; keep the mailbox address as it is unless you host your own.
3. The phone shows the sync space it's joining and the devices already in it. Continue only if you recognise every one of them - they can read what the phone sends, and the phone shows their hosts and vault.
4. Both screens show a verification code. If they're the same, choose The codes match on the phone, then They match on your computer.

The phone then opens on the Agents tab and asks whether it may show notifications. Both devices need an up-to-date Synapse, the phone's clock must be within 5 minutes of the right time, and a mailbox you host yourself must use https://.

What the phone gets

The phone receives your hosts and groups, snippets, vault passwords and SSH keys, per-host credentials and your terminal colours - whatever your computers sync. Vault items only reach it if a computer syncs the Vault category (Devices → What to sync). API keys and your other settings never go to the phone.

Answering your agents

On your computer, turn on the Agent hub service, then Show agents on my phone under Settings → AI → Agent hub (off by default; it needs sync and an unlocked vault). Your computer then sends a short summary of each agent - its name, host, status and any question it's waiting on, with secrets removed and no terminal output - end-to-end encrypted.

• The Agents tab lists agents that need you first, then every computer's agents.
• Open one to approve or decline with big buttons, choose an option, type an answer, or send a new instruction to an agent that's waiting for one.
• Your computer applies the answer on its next check, usually within a few seconds. Without a connection the phone keeps it and sends it when it can; answers older than 10 minutes are dropped.
• An approval only applies to the exact command the phone showed. If the request changed in the meantime, your computer drops the answer and tells you. If your computer couldn't show the full request on the phone, you can only decline from there - approve it at the computer.

Notifications ("Claude Code needs you") name the agent and the computer, never the question. They come from the phone checking in: every few seconds while the app is open, and in the background as often as the phone allows - on Android about every 15 minutes at best. There are no push notifications yet. Turn them off in the app's Settings → Notifications.

SSH on the phone (Android)

Open a host on the Hosts tab and choose Connect. The phone signs in with the host's password or vault SSH key from your synced vault, after Face ID, your fingerprint or the phone's passcode. A host without a saved password still connects: the server asks and you type it. Two-factor codes and key passphrases are asked for the same way.

• Host keys: the first connection to a server shows its fingerprint and asks you to Trust it. A changed key gets a full-screen warning, where Cancel is the default. The phone keeps its own trusted keys (Settings → SSH → Trusted host keys); they aren't synced.
• The keyboard bar has Esc, Tab, sticky Ctrl and Alt, arrows, Home, End, Page Up and Down, Paste and a Tools key with command packs (tmux, System, Git, Docker, WP-CLI), your synced snippets and tmux shortcuts. Commands that change something are shown for a last look before they run.
• Pasting strips control characters, and text with line breaks is shown first ("Paste 3 lines?").
• Sessions stay open while you use the rest of the app and keep their last 1 MiB of output. A dropped connection offers Reconnect, which asks for your face, fingerprint or passcode again.

The phone shows a message instead of connecting for hosts it can't handle yet:

• jump hosts and HTTP or SOCKS5 proxies;
• hosts that sign in with the SSH agent on your computer, a saved identity, or a key file that only exists on your computer - import the key into the vault and link it to the host instead;
• Telnet and serial hosts.

Limits and safety

• Read-only: hosts, snippets and the vault can't be edited on the phone. Its only writes are your answers to agents.
• Not yet: file transfers (SFTP), port forwarding, jump hosts, push notifications and SSH on iPhone. Opening a desktop session from the phone comes later too.
• App lock: Synapse locks on every start and after 1 minute in the background (choose Immediately, 1, 5 or 15 minutes). Showing or copying a secret always asks again, and copied secrets are cleared from the clipboard after 30 seconds. The phone needs a screen lock set.
• On the phone: keys are kept in the phone's secure storage and synced data in an encrypted database. Android backups of the app are off.
• Removing it: Remove this phone in the app's Settings stops syncing and deletes the keys and all synced data from the phone, and your computer changes the sync key. If you remove the phone from your computer's device list instead, it deletes its data at its next sync.
• Teams: the phone doesn't join teams.