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How-to4 min read

Codex on your phone: the ChatGPT app, and other ways

How Codex works in the ChatGPT phone app, what your computer needs, and other ways to follow Codex from a phone, including next to Claude Code in Mirasim.

The same coding session on a computer and on a phone, through the Mirasim phone appThe same coding session on a computer and on a phone, through the Mirasim phone app

The short answer

OpenAI puts Codex in the ChatGPT mobile app for iOS and Android. Open Codex there and either start a task in Codex Cloud, or connect to a Mac or Windows PC running the ChatGPT desktop app and keep working in its projects. From the phone you can follow progress, send instructions, approve commands and review diffs.

  1. Set up on the computer

    In the ChatGPT desktop app: Settings › Connections › Control this Mac or PC

  2. Scan the QR code

    Sign in to the same ChatGPT account and workspace on the phone

  3. Open Codex on the phone

    Pick the computer and a project, or Cloud and an environment

OpenAI's guide notes that mobile access is set up from the ChatGPT desktop app, not from the Codex CLI or IDE extension, and the computer has to stay awake and online. Availability depends on rollout and workspace settings.

Four ways to use Codex from your phone

Where Codex runsWhat you needOther agents
ChatGPT app › CloudOpenAI's cloud (Codex Cloud)A published cloud environment from your GitHub repositoriesCodex only
ChatGPT app › your computerYour Mac or Windows PCThe ChatGPT desktop app on that computer, awake and signed inCodex only
SSH from a phone terminalYour computer or serverA terminal app on the phone and a way to reach the machineAny terminal agent
Mirasim phone appYour computer (macOS, Windows or Linux), or a team space we hostA Mirasim account; your ChatGPT sign-in, API keys or Mirasim creditClaude Code, Kimi Code and seven more

Article · Codex Cloud: how it works, and when to use a shared space instead → How Codex Cloud environments and tasks work.

Article · The Codex app: where to get it now, and running Codex next to other agents → Where to get Codex on desktop, in the terminal and in your editor.

Using Mirasim's phone app

  1. Run Codex in Mirasim

    On your computer, or in a team space

  2. Install the phone app

    Android APK, or iPhone through TestFlight; sign in with the same account

  3. Pick up the session

    The same Codex session, next to your Claude Code ones

On the phone you can read sessions, send messages, images and files, answer the agent's questions and permission requests, and get notified when your turn finishes. The code stays on your computer, no ports need opening, and a team space we host keeps running after you close your laptop.

Chapter 20 · Claude Code and Codex on your phone, other computers and SSH servers › Use your computer's agents from your phone →

Questions

Is there a Codex app for iPhone or Android?
Codex is inside the ChatGPT app for iOS and Android rather than a separate app. Open Codex in ChatGPT.
Does my computer need to stay on?
For a connected computer, yes: OpenAI's guide says the host must be awake and online. Codex Cloud and a Mirasim team space we host keep running without it.
Can I control Codex on a Linux machine from my phone?
ChatGPT's remote access works with hosts running the ChatGPT desktop app on macOS or Windows; that app can also open projects on an SSH host. Mirasim runs on Linux too, and its phone app follows sessions there.
Can I follow Codex and Claude Code from the same phone app?
In Mirasim, yes: its phone app lists your Codex, Claude Code and other agents' sessions together.

Article · Claude Code Remote Control, and other ways to use Claude Code from your phone → Claude Code's Remote Control, and other ways to use Claude Code from your phone.

Sources

Codex details were checked against OpenAI's documentation on November 8, 2026: learn.chatgpt.com/docs/mobile, /docs/remote-connections and /docs/cloud. Codex changes quickly, so check those pages for the latest.

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