OpenAI has brought its Codex coding assistant directly into the ChatGPT mobile app, letting developers keep tabs on their coding projects from anywhere. The feature, rolled out Thursday in preview mode, works on both iOS and Android devices. Users can now access their Codex live environments across multiple devices, monitor ongoing work, and jump in to approve commands or switch models on the fly. The company emphasized that this isn't just about remotely triggering single tasks. According to OpenAI, developers can now "work across all of your threads, review outputs, approve commands, change models, or start something new" right from their phones. The integration marks a significant expansion of what developers can accomplish without being tied to their desktops. OpenAI has been on a steady release cadence with Codex over the past several months. Last month, the company added background running capabilities for desktop users, enabling the tool to handle tasks autonomously while users focus elsewhere. Earlier this month, OpenAI launched a Chrome extension that lets Codex operate within live browser sessions. Anthropic fired back in February with its own Remote Control feature for Claude Code, allowing users to monitor that tool's work remotely as well. The back-and-forth between OpenAI and Anthropic reflects intensifying rivalry in the agentic coding space. While Anthropic's Claude Code has built a strong following among businesses and developers over the past year, both platforms continue to attract substantial user bases. The competition shows no signs of slowing down as both companies race to deliver the most capable and convenient coding assistants on the market.