Cal AI Co-Founder Raises $10M for Persona, a Privacy-Focused AI Assistant with a $179 Wearable Band
At 19, Cal AI co-founder Zach Yadegari raised $10M for Persona, an AI agent that handles bookings, email and purchases. Its $179 band ships in December 2026, activates by button or wrist flick, and promises encrypted data and no sales to advertisers.
Zach Yadegari, the 19-year-old co-founder of calorie tracking app Cal AI, has launched a new AI assistant startup called Persona and raised $10 million in funding. Vine Ventures led the round, with Z Fellows founder Cory Levy and Collective Global also participating. The announcement came in October 2026.
Persona functions as a personal AI agent — similar to Instinct or Meta’s Muse — capable of ordering food and rides, booking travel, managing email, and answering questions. The startup is also developing a $179 wearable band, expected to ship in December 2026, giving it a hardware dimension comparable to Bee, the wearable AI device Amazon acquired in 2025. Unlike Bee, Persona’s band will not operate as ambient AI; it activates via a button press or a wrist flick, rather than listening continuously.
Yadegari says privacy is a central design priority. User data is encrypted in transit and at rest, stored in Persona’s cloud rather than on the device, and users can request deletion of their data. The company says it will not sell user data to advertisers or data brokers. The agent is also being built with safeguards against phishing and prompt-injection attacks. Purchases require user approval and are processed through external providers such as Stripe Link, with the agent unable to access credit-card details directly.
The startup’s current revenue model relies on advertising shown during shopping research. Yadegari says the agent will not know which results are sponsored, so its recommendations remain based on user preferences rather than ad placement.
Persona is currently available as a free beta through iMessage, with a few thousand users already signed up. The band has generated five figures in preorder revenue ahead of its December launch. A standalone app is also in development.
Yadegari’s path to Persona runs through Cal AI, which MyFitnessPal acquired for an undisclosed sum after the app surpassed $30 million in annual revenue in under two years. He left MyFitnessPal in June 2026 and began work on Persona shortly after. Before Cal AI, he sold his first business for $100,000 at age 16.