One of the most significant announcements was the Realtime API, which enables developers to create apps with low-latency, AI-generated voice responses. This feature bears some resemblance to ChatGPT's Advanced Voice Mode, but with some key differences. The Realtime API offers six distinct voices, which are not compatible with third-party voices to prevent copyright issues. This feature is expected to revolutionize the way developers build voice-enabled applications, allowing them to create more engaging and interactive experiences for users.