Codex for mobile lives inside the ChatGPT mobile app. Your phone can start, steer, approve, and review Codex work, but the connected Codex App host still supplies the project files, local tools, credentials, browser state, plugins, permissions, and execution environment.
As of May 18, 2026, OpenAI describes Codex for mobile as an iOS and Android preview in supported regions. The current remote-connection setup path checked on that date uses a Mac host running the Codex App; OpenAI's product post says Windows host connection is coming soon, even though the Codex desktop app itself is available on Windows.
| Surface | What it owns | Use it when |
|---|---|---|
| ChatGPT mobile | Starts, steers, approves, reviews, and notifies | You need to supervise Codex away from the desk |
| Codex App host | Files, repo state, local tools, credentials, browser state, plugins, permissions, and execution | You need host-side context and tools to do real work |
| Codex cloud or web | Hosted tasks and review flows | You do not need a specific local host session |
| CLI or IDE extension | Editor-adjacent coding flow | You are actively working at the machine |
Stop rule: if Codex is missing in ChatGPT mobile, check the mobile app version, account and workspace, Codex access, host awake/online status, admin Remote Control setting, preview rollout, and platform caveat before changing prompts.
What has to be true before mobile setup
The mobile route depends on two things being true at the same time: the ChatGPT mobile app must expose Codex for your account and workspace, and a connected host must be ready to do the work. Updating only the phone app is not enough if the host side is asleep, signed into another workspace, or blocked by admin policy.
OpenAI's Codex for mobile page points readers to ChatGPT on iOS and Android. OpenAI's remote connections documentation is the setup contract for connecting a phone to a Codex App host. Those are two halves of the same route: the phone gives you control, while the host gives Codex the environment.
| Requirement | Why it matters | Quick check |
|---|---|---|
| Latest ChatGPT mobile app | The mobile surface appears inside ChatGPT, not as a separate verified Codex phone download | Update ChatGPT from the iOS App Store or Google Play, then reopen the workspace |
| Codex access for the account | Mobile cannot expose a product your account or plan does not have | Check Codex from the desktop or web surface first |
| Same account and workspace | Remote control follows the workspace boundary | Confirm the phone and host are signed into the same OpenAI account and workspace |
| Codex App host awake and online | The host provides files, tools, credentials, browser state, and execution | Keep the host running the Codex App and reachable |
| Current Mac host setup path | OpenAI's current setup docs describe Mac host setup and device control | Use the Mac host path unless OpenAI updates the Windows-host connection status |
| Admin Remote Control setting | Business, Edu, and Enterprise workspaces may restrict remote access | Ask an owner to confirm Remote Control and Codex access settings |
If any row fails, fix that row before testing prompts. Prompt changes cannot solve an account, workspace, host, admin, rollout, or platform blocker.
How to connect and verify safely
Begin with a host task that cannot damage anything. A good first test is a read-only repository inspection, a small typo fix in a disposable branch, or a thread that asks Codex to summarize a file and wait for approval before touching code. The goal is to test the approval and review loop, not to prove that the phone can drive a high-risk change.
The setup sequence should stay narrow:
- Open the Codex App on the host and confirm the project or workspace you want to use.
- Make sure the host is awake, online, and signed into the same OpenAI account and workspace as ChatGPT mobile.
- Open ChatGPT mobile and switch to the same workspace.
- Open Codex from the mobile surface and choose the connected host or thread.
- Start a tiny task, then send one follow-up instruction from the phone.
- Approve only a low-risk action and confirm you can review output, terminal text, diff, test result, or screenshot from mobile.
- Turn on notifications only after the first small approval path behaves as expected.
Treat that first task as a systems check. If the host cannot provide the right files, if the phone cannot see the thread, or if an approval request looks broader than the task requires, stop and correct setup before adding real work.
What your phone can do, and what stays on the host
The phone-side verbs are control verbs. OpenAI describes mobile Codex as a way to start or continue threads, steer work, approve commands or actions, review outputs, see diffs and tests, inspect terminal output or screenshots, receive notifications, and switch between hosts or threads. That makes it useful when a long-running task needs supervision while you are away from the machine.
The host-side nouns are the important safety detail. Project files, repository state, local tools, credentials, browser state, plugins, Computer Use configuration, MCP setup, permissions, and the actual execution environment remain tied to the connected host. A phone approval can therefore affect real host resources. The phone is convenient, but it is not a separate sandbox.
This host-owned model also explains why mobile approval and host-side GUI control are different layers. If the host has Computer Use configured, Codex may be able to observe or act on approved GUI or browser surfaces from that host. That does not make Computer Use phone-native. The narrower Codex Computer Use guide covers when visual app control is worth the extra permission and when a structured route is safer.
Use the mobile surface for supervision:
- checking whether Codex is waiting on a decision
- sending a small steering instruction
- approving a command you understand
- reviewing a diff before merge or commit
- seeing whether tests passed
- deciding whether to continue, pause, or move back to the desktop
Do not use the mobile surface as a reason to approve work you would not approve at the host. The connected environment is still the source of truth.
Why Codex may be missing in ChatGPT mobile
Missing mobile access is usually a route issue, not a model issue. Work through the access stack from the most local check to the most external one.
| Symptom | Likely cause | Next move |
|---|---|---|
| ChatGPT mobile has no Codex entry | App version, preview rollout, region, account, or workspace mismatch | Update ChatGPT, restart the app, switch to the correct workspace, then check Codex on another surface |
| Mobile sees Codex but no usable host | Host is asleep, offline, not running Codex App, or signed into another workspace | Wake the host, open Codex App, confirm the same account and workspace |
| A workspace user cannot connect | Admin controls block Codex or Remote Control | Ask a workspace owner to check Codex local/cloud and Remote Control settings |
| Windows machine has Codex desktop but phone connection fails | Desktop app availability and Windows-host mobile connection are separate facts | Use a supported host path until OpenAI updates Windows-host connection status |
| Approval requests look too broad | The task moved outside the intended host or permission lane | Cancel, narrow the instruction, and restart with a safer target |
OpenAI's enterprise admin setup documentation matters even for a reader who is not an admin, because workspace policy can decide whether a user sees a route at all. When a feature is visible to one teammate and absent for another, workspace and access settings are often more plausible than prompt behavior.
iPhone, Android, Mac, and Windows do not answer the same question
The platform split is easy to misread because the same product family spans phone, desktop, and hosted surfaces. Keep these questions separate.
| Question | Current answer as of May 18, 2026 | What not to infer |
|---|---|---|
| Can I use Codex from iPhone? | OpenAI describes Codex for mobile as available in preview through ChatGPT mobile on iOS in supported regions | Every iPhone account has it immediately |
| Can I use Codex from Android? | OpenAI describes the preview through ChatGPT mobile on Android in supported regions | Every Android account has it immediately |
| Does the host have to be a Mac? | The current remote-connection setup path checked on May 18, 2026 uses a Mac host running the Codex App | The requirement can never change |
| Does Codex desktop work on Windows? | OpenAI's Codex App docs describe the desktop app on macOS and Windows | Windows host connection for mobile is already the same as Mac host setup |
| Can CLI or IDE extension set up mobile access? | The current remote-connections docs say setup is not available from CLI or IDE extension | CLI or IDE extension is obsolete for editor work |
For broader product changes across Codex surfaces, the OpenAI Codex March 2026 overview is the better companion. For a phone setup decision, the only platform detail that matters is which surface owns control and which surface owns the working environment.
When another Codex surface is better
Mobile is strongest when the work is already in motion and you need to stay in the loop. It is weaker when the task requires close editing, careful local inspection, or a sequence of approvals that should happen at the machine.
Choose the desktop Codex App when the project context, tools, worktrees, terminal output, screenshots, browser state, and plugins are central to the job. The desktop app is the natural place to start larger local runs, inspect risky changes, or manage multiple active threads.
Choose Codex cloud or web when hosted execution and review are enough and the job does not depend on a specific local host session. Hosted routes can be cleaner for repository tasks that do not need your local browser state, credentials, or machine-specific tooling.
Choose CLI or IDE extension when the work belongs close to the editor. If you are actively reading code, iterating on tests, or reviewing diffs line by line, the phone adds distance instead of control.
Choose Computer Use only when the host-side GUI or browser is the evidence or control surface. That is a narrower permission lane, not a general upgrade over mobile, desktop, or structured tools.
Safety rules for approving from a phone
A phone approval can feel casual because the screen is small. The effect is not small if the connected host holds real credentials, signed-in websites, local files, or production-adjacent tools. Use the same approval standard you would use at the host.
Keep these rules close:
- Approve commands only when you understand the target directory, files, and likely side effects.
- Review diffs before merge, commit, deploy, publish, or destructive cleanup.
- Treat signed-in browser actions as actions taken by you.
- Do not approve billing, account deletion, permission grants, legal acceptance, or production changes from a phone unless the task was deliberately scoped for that action.
- Stop at system prompts, admin prompts, privacy permissions, or security prompts and handle them yourself.
- Prefer a branch, disposable repo, or low-risk environment for first mobile tests.
For plan windows, quota details, and API-key differences, use the Codex usage limits guide after you know which Codex surface you are actually using. Access routing should come before limit math.
FAQ
Is there a separate Codex mobile app?
The current first-party route checked on May 18, 2026 is Codex inside the ChatGPT mobile app. Install or update ChatGPT mobile, then connect it to a Codex App host when the mobile surface and account are eligible.
Does my phone run the repository?
No. The phone controls and reviews Codex work. The connected host still owns the repository, files, tools, credentials, browser state, plugins, permissions, and execution context.
Does it work on both iPhone and Android?
OpenAI describes Codex for mobile as an iOS and Android preview in supported regions. That wording does not mean every account, workspace, region, or admin configuration sees it at the same moment.
Why can I see Codex on desktop but not mobile?
Start with app version, account, workspace, access, and rollout. Then check whether the host is awake, online, running the Codex App, and signed into the same workspace. In managed workspaces, ask an owner to confirm Codex and Remote Control settings.
Can I connect a Windows host from my phone?
OpenAI says the Codex desktop app is available on Windows, but its May 2026 product post says support for connecting to the Codex app on Windows is coming soon. Keep desktop app availability separate from mobile host-connection support.
Can I set this up from Codex CLI or an IDE extension?
The current remote-connections docs checked on May 18, 2026 say mobile access setup and device control are not available from Codex CLI or the IDE extension. Use those surfaces for editor-adjacent coding work, not for phone-to-host setup.
What should I test first after setup?
Run a low-risk task: ask Codex to inspect a file, summarize a branch, or propose a tiny change in a disposable branch. Confirm that you can steer, approve, review output, and receive notifications before using mobile approval on real changes.
When should I avoid approving from mobile?
Avoid phone approval when the action affects billing, account settings, destructive changes, signed-in production tools, legal acceptance, security prompts, admin permissions, or anything you would normally require a full-screen review to approve.