AssemblyAI's August 29, 2025, newsletter highlights several key updates and events in the realm of speech-to-text and voice AI technology. It announces an upcoming Voice Agents Hackathon in San Francisco on September 19, co-hosted by AssemblyAI, LiveKit, Rime, and Accel, where participants can compete for a $1,500 prize and a feature on the company's blog. The newsletter also introduces the In-App Playground, an in-browser tool allowing users to explore AssemblyAI's Speech-to-Text features without coding, offering functionalities like sample file testing, API snippet generation, and detailed API response inspection. Furthermore, AssemblyAI's Universal service now supports 99 languages at a flat rate with automatic language detection and speaker diarization for 95 languages. A new security enhancement, Multi-Factor Authentication, is now available to all users, providing an additional layer of account protection. The newsletter also promotes recent blog content, including insights into conversation intelligence systems, AI voice agent technology stacks, and a tutorial for building call center analytics pipelines using Python and AssemblyAI's API.