Cal AI's 19-year-old founder raises $10M for Persona, an AI assistant with a wearable band

Cal AI was acquired by MyFitnessPal in March for an undisclosed sum after it moved ahead of the older calorie app in app store rankings. MyFitnessPal told TechCrunch the deal was large enough to persuade Yadegari and his co-founders to sell after Cal AI generated more than $30 million in annual revenue in less than two years. Yadegari and his co-founders initially worked for MyFitnessPal to continue developing Cal AI, but he left the company in June and began work on his next idea. He is working with another co-founder who has not yet been announced.

Persona is a personal AI assistant similar to Instinct or Meta's Muse, but it includes a hardware component: a $179 wearable band that is expected to be available in December. The product is also similar to Bee, the wearable AI device Amazon acquired in 2025, though Yadegari told TechCrunch that Persona's device differs in several ways.

Persona will not be an ambient AI that constantly listens and records, Yadegari said. The band will have a button to activate the assistant, or users can set it to activate with a flick of the wrist. The AI model does not run on the device, and user data is not stored there. Instead, the model runs in Persona's cloud, and user data is sent there. The company says it encrypts data in transit and at rest, and users can delete their data. Persona says user conversations stay private and cannot be sold to advertisers or data brokers.

The team is also adding safeguards against phishing and prompt-injection attempts, two areas that can affect AI agents, according to AI labs such as OpenAI. Yadegari said Persona's agent cannot see a user's credit-card details, and purchases require user approval. Payments are handled through external providers such as Stripe Link, Stripe's secure wallet designed for agents.

Although user data will not be sold to advertisers, Persona's current business model relies on advertising. Yadegari said the company will show advertised products during shopping research. He said the agent will present unbiased recommendations because it will not know which items are sponsored. If a user researches office chairs, for example, "the agent knows their preferences" and will show chairs that match them, some of which are sponsored results.

Persona has launched as a free beta product in which users interact with the assistant through iMessage text messages. It has attracted "a few thousand beta users," Yadegari said. The wearable band has generated "five figures in preorder revenue." An app is also in the works. Like other consumer AI assistants, Persona can order food or rides, take notes, book travel and answer questions and emails, among other tasks.

"All of the utility apps that you use on your phone day-to-day, whether those are apps for shopping, whether it's Uber, DoorDash, your email — these are all collapsing and will collapse into a single super app powered by an AI assistant," Yadegari said. Eventually, he hopes Persona will become more proactive. "It can offer help and solve problems before you even know you have a problem, and overall be more seamless with your life, so that you don't need to stare at a rectangle in your hand all day."

Yadegari is scheduled to speak at TechCrunch Disrupt on "How to create viral growth and capitalize on it." The event takes place October 13-15 at the Moscone Center in San Francisco. Before Cal AI, he built his first business in the ninth grade and sold it for $100,000 when he was 16.