MightyMouse vs OpenAI Codex
Keep using Codex with your ChatGPT plan. Add your other agents, and your whole Mac, in one place on your phone.
Short answer: MightyMouse runs Codex on your own Mac with the ChatGPT plan you already pay for, next to Claude Code, Cursor and OpenCode, so you are not locked to one lab. You reply, approve and merge from your phone with the lid closed, and the phone also gives you the live screen, a trackpad, keys and free voice typing.
Codex is OpenAI's coding agent. It comes as a desktop app, a command line tool, an editor extension, a cloud service and a tab in the ChatGPT mobile app, and it is included in ChatGPT plans from Free to Enterprise. The ChatGPT mobile app can start tasks in the Codex cloud or on a Mac or Windows PC you have connected, follow progress, send new instructions and approve or deny commands.
MightyMouse does not replace Codex. It runs it for you on your Mac, signed in with your ChatGPT account, and puts it in the same window as Claude Code, Cursor and OpenCode. Each agent gets its own copy of the project, you review the changes, open the pull request and merge it, and your phone answers all of them. It also reaches the rest of the Mac, which the Codex phone tab does not. For the cloud side of the comparison, see MightyMouse vs Codex cloud.
Side by side
| MightyMouse | OpenAI Codex | |
|---|---|---|
| Run Codex with your ChatGPT plan | Yes, on your own Mac | Yes |
| Run Claude Code, Cursor and OpenCode too | Yes, side by side | No, Codex only |
| Each agent in its own copy of the project | Yes, its own branch | Yes, git worktrees |
| Start, follow and approve agent work from the phone | Yes | Yes, in the ChatGPT app |
| Merge the pull request from the phone | Yes | Not checked |
| Approve an agent from the lock screen | Yes, with Face ID | Not checked |
| Agents keep going with the lid closed | Yes, on your own Mac | Their guide says keep the computer awake and online |
| Live Mac screen, trackpad and keys on the phone | Yes | No |
| Free voice typing into any app | Yes, on-device Whisper | No |
| Works with no computer on | No - your Mac is the computer | Yes, Codex cloud |
| Windows and Linux | Mac only | Yes |
| Price | Free to try. Your ChatGPT plan covers Codex | In ChatGPT plans: Free, Go $8, Plus $20, Pro from $100 |
OpenAI Codex details checked 5 November 2026 from learn.chatgpt.com (formerly developers.openai.com/codex), openai.com. Prices change - check theirs before deciding.
Where Codex is the better pick
Codex cloud runs the work on OpenAI's computers, so it keeps going with your Mac shut off or nowhere near you, and it can run tasks in parallel. MightyMouse has no cloud computers for Codex: your Mac does the work, so it has to stay on (the lid can be closed). Codex also runs on Windows and Linux, and its own phone tab is built into the ChatGPT app you may already have.
If Codex is the only agent you use and you do not need anything else from your phone, the ChatGPT app is enough.
Where MightyMouse is the better pick
Every agent, one phone. Codex for one task, Claude Code or Cursor for the next. Your plans stay yours, and all of them answer to the same phone.
The whole Mac, not only the agent. A dialog the agent did not expect, a browser tab to check: open the phone and you have the live screen, a trackpad, the keyboard and voice typing.
Lock screen to merge. An agent's question lands on your lock screen. Approve it with Face ID, read the reply, merge the pull request, all from the couch.
Using both works fine
MightyMouse runs your own Codex, signed in with your ChatGPT account, so nothing is paid twice. Keep the Codex app for what it is good at and use MightyMouse when you want your other agents or the Mac itself from the phone.
More on the phone side in Codex from your phone, and how this works for other agents in Claude Code on iPhone and Cursor from your phone.
Codex and your other agents on your Mac, your Mac in your pocket.
macOS, Apple Silicon and Intel. No card to try it.
Common questions
Do I need an AI subscription?
No. Connect a Claude, Codex, Gemini or OpenCode account you already pay for and MightyMouse costs nothing. Have none? Sign up and use the built in option, no card needed. Voice transcription is free either way because it runs on your Mac.
Do I pay for Codex twice?
No. MightyMouse runs Codex with the ChatGPT account you already have, so your plan covers it.
Does the ChatGPT app already control Codex from my phone?
Yes. OpenAI's ChatGPT mobile app can start Codex tasks in the cloud or on a connected Mac or Windows PC, follow progress, and approve or deny commands. MightyMouse adds Claude Code, Cursor and OpenCode, plus the live Mac screen, trackpad and voice typing.
Does the Mac have to stay on?
Yes. The agents run on your Mac, which can sit with the lid closed. If you need work to run with no computer on, Codex cloud is the better fit.
Want Codex and your other agents in your pocket? MightyMouse runs them on your own Mac and puts the whole Mac on your phone. Free to try, no card.