OpenAI has officially integrated its Codex coding tool into the ChatGPT mobile app, marking a significant step in the ongoing battle with Anthropic for dominance in AI-powered software development. Available now in preview for all ChatGPT plans on both iOS and Android, the update enables developers to remotely monitor and manage their coding environments directly from their smartphones.
The mobile integration does not run Codex natively on the phone. Instead, it acts as a remote interface to the user's pre-configured machine—whether a Mac mini, laptop, or cloud-based workspace. Through a secure relay layer, the ChatGPT app syncs active session state, credentials, and permissions without exposing those resources to the public internet. Developers can review outputs, approve commands, switch models, initiate new tasks, and work across multiple threads, receiving status updates, screenshots, and test results in real time.
This launch follows a series of rapid enhancements from OpenAI, including last month’s debut of background operation for Codex on desktop and a Chrome extension earlier in May that allows the agent to function within live browser sessions. The mobile expansion is widely seen as a direct competitive response to Anthropic’s Claude Code, which has offered a similar Remote Control feature since last fall, enabling developers to monitor agentic coding sessions from their phones.
Both companies are racing to establish their tools as the default platform for AI-assisted development. While Codex has been available for approximately a year, Claude Code has gained substantial traction among businesses and tech professionals. The new mobile capability addresses a common complaint among Codex users—the lack of phone control—which some cited as a reason for switching to competing platforms.
Beyond immediate competition, the move aligns with OpenAI’s broader vision for a unified app. In March, the company confirmed it is building a single desktop application that will combine ChatGPT, Codex, and its Atlas web browser. For developers, the mobile integration promises greater flexibility in managing remote, asynchronous workflows, potentially reshaping how coding tasks are executed in an increasingly mobile-first world.
