Codex vs Claude Code: continuing work across devices

Choose the continuity problem first

If you are searching for Codex vs Claude Code because you switch between a desk, laptop and phone, compare a concrete action: return to a saved conversation, answer an active session remotely, or move execution. Those actions require different state. A useful evaluation keeps the conversation, working files and execution location visible together.

Resuming a CLI conversation

OpenAI’s command reference scopes codex resume --last to the current directory unless --all is included. A different working directory can prompt a choice between the current directory and the saved one. Check that choice before a new instruction.

Anthropic’s workflow reference describes locally saved conversations: claude --continue returns to recent work in the current directory, while claude --resume opens a picker. These commands establish a return to saved history; they do not by themselves prove that another machine has the same uncommitted files.

For a practical Codex example, read the CLI resume guide.

Mobile access and the execution host

OpenAI’s remote guide describes pairing a phone with an available desktop host. It also describes Handoff between a local computer and a connected remote host with a matching saved Git project; Handoff into a Codex Cloud environment is unsupported.

Anthropic’s Remote Control guide describes a phone or browser connecting to a Claude Code process on your computer. In an existing session, /remote-control enables that connection after its confirmation. The computer and process must remain available. A Claude Code cloud session runs elsewhere; opening the same web interface does not establish the same execution location.

Before leaving, open the intended session from your phone and verify the latest reply, pending question and current files. This is a suggested evaluation, not a completed multi-device test of either product.

How ordinary ChatGPT chats differ

The OpenAI product guide documents Chat sync between web and desktop and Cloud Work continuation across web, mobile and desktop. Ordinary chat access is therefore a different requirement from restoring a local coding workspace. Finding a conversation in an account does not establish which computer has its unfinished code.

Use a continuity comparison when your missing piece is the project state, execution host or next action. Start with the product’s existing account-sync documentation when your question is simply where a saved chat appears.

A small comparison you can actually run

1. Choose a disposable repository with an invented change and give the conversation a recognizable name.
2. Record the changed files and last response. Leave one clear question awaiting an answer.
3. Open the intended second device and identify both the session and execution host.
4. Check that the unfinished diff is present, then answer the question once.
5. Return to the first device and confirm which session and files now represent the work.

If a step fails, record whether the conversation, files or host were missing. That evidence is more useful than a general claim that a tool “syncs.” For moving computers, read the session-continuity guide; for phone setup, read Codex on iPhone and Android.

More Codex guides

Browse cloud, mobile and session-continuity guides.