Zach Yadegari, the teenage entrepreneur who co-founded the popular calorie-tracking application Cal AI, has launched a new artificial intelligence startup called Persona and secured $10 million in early funding. The financing round was led by Vine Ventures, with participation from Cory Levy, founder of Z Fellows, and investment firm Collective Global.

Yadegari first made headlines earlier this year when fitness platform MyFitnessPal acquired Cal AI for an undisclosed amount. The deal came after Cal AI surpassed MyFitnessPal's own app in App Store rankings - a remarkable feat given that Cal AI had only been operating for less than two years. Despite its short lifespan, the app had already reached more than $30 million in annual recurring revenue by the time the acquisition was finalized, according to statements MyFitnessPal made at the time of the deal.

Following the acquisition, Yadegari and his fellow co-founders initially stayed on with MyFitnessPal to continue building out Cal AI. However, he departed the company in June of this year and quickly shifted his focus to a new venture. He is currently working alongside another co-founder whose identity has not yet been publicly disclosed.

A Personal AI Assistant with a Hardware Twist

The result of that next chapter is Persona - a personal AI assistant that draws comparisons to products like Instinct or Meta's Muse, but with an added physical component. Persona is developing a wearable band, priced at $179, which is expected to ship in December.

The inclusion of a hardware element places Persona in similar territory to Bee, the wearable AI device that Amazon acquired in 2025. However, Yadegari is quick to point out meaningful differences between the two products. Unlike ambient AI devices that are continuously listening and recording their surroundings, Persona's band will not operate passively in the background. Instead, users can activate the assistant either by pressing a physical button on the device or by using a wrist-flick gesture - giving users direct control over when the assistant is active.

Privacy and Security at the Core

Privacy has been positioned as a central pillar of Persona's design philosophy. Rather than processing data or running its AI model directly on the device, Persona operates through a cloud-based infrastructure. User data is transmitted to and stored within that cloud environment. To protect that data, the company says it employs encryption both during transmission and while data is at rest. Users also retain the ability to delete their personal data at any time.

The company has pledged that conversations and personal information will remain private and will not be shared with advertisers or sold to data brokers - a commitment that distinguishes it from many ad-supported digital services.

On the security side, the team is also building in protections against phishing attacks and prompt-injection exploits - two vulnerabilities that AI agents are known to face, as acknowledged by leading AI research organizations including OpenAI. Additionally, Yadegari noted that Persona's agent will not have access to a user's credit card details. Any purchases made through the assistant will require explicit user approval, with payment processing handled through external providers such as Stripe Link, which is Stripe's secure payment wallet built specifically for agent-based transactions.

Advertising Model with a Twist

Although user data will not be sold, the startup's current revenue model does incorporate advertising. When users conduct shopping research through the assistant, Persona will surface sponsored products alongside organic results. Yadegari argues that this approach preserves objectivity because the AI agent itself will not be aware of which items carry paid placement. The assistant will surface recommendations based solely on a user's stated preferences and behavioral patterns, with sponsored listings blended into those results without influencing the agent's underlying logic.

As an example, Yadegari explained that if a user is looking into office chairs, the agent would draw on what it already knows about that person's tastes and requirements, returning a list of relevant options - some of which may be sponsored - without the agent prioritizing paid results over genuinely relevant ones.

Early Traction and Product Availability

While the wearable band is still several months from reaching consumers, Persona has already launched a free beta version of its assistant. Currently, users interact with the AI through iMessage text conversations. That beta has attracted several thousand users so far, according to Yadegari. The band itself has also generated five-figure revenue through preorders ahead of its December launch date. A standalone app is also in development, though no specific release date has been announced.

In terms of functionality, Persona is designed to handle a wide range of everyday tasks. The assistant can order food and transportation, take notes, book travel, respond to emails, and answer general questions - capabilities broadly in line with what other consumer AI assistants currently offer.

A Vision for the Future of Apps

Yadegari's broader ambition for Persona extends beyond a simple utility assistant. He believes the proliferation of individual apps is approaching a tipping point, and that a unified AI-powered platform will eventually absorb the functions currently spread across dozens of separate applications.

"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."

Looking further ahead, he envisions Persona evolving into a more proactive presence in users' lives - one that can anticipate needs and address issues before users are even aware of them. As he put it, the goal is for the assistant to be "more seamless with your life, so that you don't need to stare at a rectangle in your hand all day."

A Track Record That Starts in High School

Yadegari's entrepreneurial history predates Cal AI by several years. Before building the calorie-tracking app that would eventually be acquired by one of the fitness industry's most established platforms, he launched his first business while in ninth grade. He sold that company for $100,000 at the age of 16 - a milestone that set the tone for what has since become a notable early career in consumer technology and AI.

With $10 million in fresh capital, a growing beta user base, and a hardware product on the horizon, Yadegari is moving quickly to establish Persona as a credible player in the increasingly competitive personal AI assistant market.