OpenAI testing bidirectional voice experience in ChatGPT app

OpenAI is testing a new bidirectional voice mode in the ChatGPT app, unofficially labeled 'gpt-bidi-1,' that aims to break the rigid turn-taking of current voice assistants. The model can speak while listening, be interrupted naturally, and correct itself mid-utterance in real time — moving voice interaction closer to natural human conversation rather than a walkie-talkie exchange.

The push reflects a wider industry bet that voice is the next major interface battleground: Andrew Ng launched a course on building reliable, low-latency voice agents the same week, and Apple's overhauled Siri AI is reframing voice expectations on phones. Bidirectional, interruptible voice is technically hard because it requires simultaneous listening and generation with fast barge-in handling — the same tradeoff between fast voice-to-voice models and accurate-but-laggy STT pipelines that practitioners cite.

Separately, OpenAI confirmed it will retire older models from ChatGPT: GPT-4.5 by June 27, 2026, and o3 by August 26, 2026 — part of an ongoing model-lineup consolidation that has drawn 'model-version-fatigue' grumbling (r/OpenAI's 'GPT 5.6 Cancelled' thread, 387 upvotes). The o3 retirement is notable given a NEJM AI study this week credited o3 with diagnosing 18 rare-disease patients. Watch whether gpt-bidi-1 ships broadly and how its latency compares to Gemini Live and Siri AI.