Elon Musk announced that his AI startup xAI will take legal action against Apple, alleging antitrust violations related to App Store rankings. Musk claims Apple's practices favor OpenAI's ChatGPT, making it difficult for other AI apps, like xAI's Grok, to compete for the top spot. OpenAI's CEO Sam Altman responded to Musk's claims, emphasizing the need for transparency in competition.