Introduction

C3 Mobile lets you control the coding agents running on your machines from your phone. Answer permission prompts, send follow-up instructions, watch live terminals, and manage workspaces across every machine you own — through one end-to-end encrypted connection to a hub you host yourself.

NOTE — > C3 Mobile is beta software. Android and Linux hosts (x64 and ARM64) are the qualified beta platforms; iOS, macOS, and Windows builds exist but are still being qualified.

The control plane

C3 Mobile is user-owned infrastructure. Nothing passes through anyone else's cloud:

• C3 Mobile — the phone client (iOS and Android). One foreground connection to your hub discovers and controls any number of machines.
• C3 Desktop — the Linux setup assistant and desktop Herdr client. It can provision the same hub, enroll devices, and operate the same fleet from a larger control room.
• C3 Bridge — a small daemon (c3bridge) on each machine you want to control. It adapts Herdr, the terminal workspace manager that hosts your agents, and relays commands, events, and terminal output.
• C3 Hub — a self-hosted NATS relay you run on any machine you own (a Raspberry Pi is enough). It is provisioned by the c3sync CLI and routes only ciphertext.

C3 Mobile ── pinned WSS + E2EE ── C3 Hub ── TLS + E2EE ── C3 Bridge ── Herdr ── your agents

Your agents — Claude Code, Codex, and any other CLI agent — run inside Herdr workspaces on your machines, exactly as they do today. C3 never talks to the agent vendor; it gives you a remote control for the terminals the agents already live in.

What you can do from the phone

• Triage at a glance — the Signal screen maps every host and queues the agents that are blocked waiting on you.
• Unblock agents — open a session, read its state, answer the permission prompt, or send the next instruction.
• Drive workspaces — create workspaces, tabs, and panes on any connected host.
• Watch the real terminal — a live, streaming PTY view of any pane, resized to your phone.
• Stay private — every message is end-to-end encrypted on your devices; the hub and push notifications never carry prompts, terminal content, or filenames.

How it stays yours

The hub sees subjects, sizes, and timing — never content. The phone pins your hub's certificate authority and refuses everything else. Pairing between phone and each bridge uses one-time QR codes with mutual key confirmation, and either side can be revoked independently. Read the security model for the full picture, including what C3 Mobile does not protect against.

Start here

1. Check the requirements and components.
2. Set up your hub, either from C3 Desktop or the CLI.
3. Set up a bridge on each machine you want to control.
4. Enroll your phone and pair it with each bridge.

TIP — > Already running C3Sync? C3 Mobile uses the same hub — no second server. The two products live in isolated accounts on it, so mobile control traffic can never read your synced session data. See the architecture.