On this week’s “Marketplace Tech Bytes: Week in Review,” we take a look at Nvidia's changing investment relationship with OpenAI. Plus, a stormy start for the new U.S. version of TikTok. But first, SpaceX, one of the world’s largest rocket companies, announced this week that it’s buying xAI, a two-and-half-year-old artificial intelligence startup. Both companies are controlled by Elon Musk. The new company is reportedly valued at $1.25 trillion. It means the chatbot Grok, the satellite internet company Starlink, and the social media firm X are all going to co-exist under the same rocket hangar. Marketplace’s Stephanie Hughes spoke with Paresh Dave, senior writer at Wired, about what adding these companies together equals.

A landmark lawsuit that accuses social media companies of intentionally designing their platforms to be addictive — and causing harm to children and teenagers' mental health — is in court this week in Los Angeles.

The defendants in this case are Meta and YouTube, both of which dispute the allegations. Snap and TikTok both settled in advance of the trial.

Some are calling this social media's "Big Tobacco" moment. Eric Goldman, co-director of the High Tech Law Institute at Santa Clara University, discusses this as well as a series of lawsuits against the social media giants.

You can get a pretty good workout plan from a chatbot, but the tech is also being incorporated into all kinds of existing fitness apps, from Apple's Workout Buddy, which motivates you through earbuds, to the Fitbit AI health coach, to Peloton's AI-enabled camera that tracks your form.

Nicole Nguyen, personal tech columnist at The Wall Street Journal, gave some of the most popular ones a spin. She spoke with “Marketplace Tech” host Meghan McCarty Carino about her experience.