SigilTTY: SSH & Terminal

About

SigilTTY is a native AI terminal for iPhone, iPad, and Mac — an SSH client built for the era of coding agents. Attach to the agents already running on your own servers, see which ones are working and which are stuck, get pushed the moment one needs you, and answer out loud. Everything a terminal still has to do — shells, SFTP, tunnels, keys — is here too, synced across your devices through iCloud. To be clear about what this is: SigilTTY does not run the AI, and there is no chatbot inside it. Your machines run the agents, right where your code, your tools and your credentials already are. SigilTTY is the control room you carry. Built on a GPU-accelerated terminal (powered by Ghostty) and the battle-tested libssh2 engine, SigilTTY feels instant and looks sharp on every screen. YOUR AGENTS, WHEREVER YOU ARE • Attach to the AI coding agents that herdr manages on your servers — each one is an ordinary terminal tab with a live status dot • Agents mode gathers every agent on every server into one tree in the sidebar on iPad and Mac; on iPhone your agents get a tab of their own • Be told when an agent is blocked or done, even while SigilTTY is closed. Offline alerts are encrypted end-to-end on your own server; our open-source relay only ever sees ciphertext • Answer by voice in an agent session: bring your own transcription key — Volcengine, iFlytek, or any compatible speech-to-text endpoint. Audio goes only to the endpoint you configured, and the transcript is typed into the prompt for you to read — it never sends itself • Paste or drop files straight into the terminal — they upload over SFTP and the remote path is typed out for the agent to read • Agent features need the open-source herdr 0.8.0 or later on your server STILL A REAL TERMINAL • Native, GPU-accelerated rendering — smooth even under heavy output • Multiple sessions with tabs, plus full menu commands and shortcuts on Mac • Hundreds of Ghostty/iTerm2-compatible color themes, with dedicated CJK font selection • Command snippets you can send with a single tap CONNECT YOUR WAY • SSH with password or private-key authentication • Telnet for legacy devices and equipment • Serial console over USB on Mac • Jump hosts / bastion chains to reach private networks • Quick Connect for ad-hoc user@host sessions FILES & TUNNELS • Full SFTP file browser — upload, download, rename, delete • File preview: code with syntax highlighting, images, PDFs and documents with Quick Look • Transfers run in their own session and never block your terminal • ZMODEM: run sz or rz on the remote side, right in the terminal • Local (-L) and remote (-R) port forwarding • SSH agent forwarding — the app answers the agent protocol itself, with no extra setup SECURITY FIRST • Credentials live in the Keychain, never in plain text • Optional Face ID / Touch ID protection for private keys • Sign in with a hardware security key over USB-C or NFC — FIDO2/WebAuthn, tested with YubiKey. The private key never exists in software • Trust-on-first-use host key verification warns you the moment a server's identity changes • A remote host asking to read or write your clipboard has to ask you first • Key Handoff: hand a private key to another device over your local network, end-to-end encrypted and confirmed with a verification code — the key never leaves your LAN • No ads. No analytics. No tracking. SYNCS EVERYWHERE • Your servers, folders, snippets, keys, known hosts and agent records sync securely with iCloud • Start on your Mac, pick up on your iPhone • Interface in English and Simplified Chinese SigilTTY is free to download. Have feedback or a feature request? Reach us at support@sigiltty.com.