The 19-year-old who sold Cal AI to MyFitnessPal is back with Persona, a screenless wristband that sends voice requests to an AI agent built to finish tasks for you.
Zach Yadegari, the 19-year-old co-founder of calorie app Cal AI, has raised $10 million for a new startup called Persona. MyFitnessPal bought Cal AI in March 2026, and Yadegari left in June to build an AI assistant that does tasks for you, like booking rides, ordering food, sending emails and making calls.
Its hardware is a $179 screenless wristband, due in December, that you activate with a button or a wrist flick. It isn't always listening. Until it ships, a free beta runs through iMessage and already has a few thousand users.
The band's battery and microphone claims have not been independently tested yet, so the free beta is the low-risk way to try it.
Months after selling his calorie-counting app to MyFitnessPal, 19-year-old Zach Yadegari has raised $10 million for his next act: an AI assistant you wear on your wrist. The startup is called Persona, and its $179 band has no screen at all. You press a button or flick your wrist, say what you need, and an AI agent tries to get it done.
If you’ve wondered when AI assistants would stop just answering questions and start doing chores, this is one of the bets. Persona wants to book rides, order food, handle email and make calls for you. That also means handing a young startup access to your accounts, your messages and, in some cases, your money, so the details matter.
Zach Yadegari co-founded Cal AI, an app that estimates calories from a photo of your meal. It climbed past MyFitnessPal in the app store rankings, and in March 2026 MyFitnessPal bought it for an undisclosed sum. At the time, MyFitnessPal said Cal AI had passed $30 million in annual revenue in under two years.
Yadegari and his co-founders joined MyFitnessPal after the sale, but he left in June and started on Persona straight away. He’s working with another co-founder who hasn’t been named yet. Cal AI wasn’t his first exit, either. He built a business in ninth grade and sold it for $100,000 at 16. Much of the coverage of this round has also focused on another detail: he was turned down by 15 universities before Cal AI took off.
The $10 million round was led by Vine Ventures, with Z Fellows founder Cory Levy and Collective Global joining in.
The Persona Band is a screenless wristband that works as a direct line to Persona’s AI assistant. It isn’t trying to be a smartwatch. There are no maps, fitness tracking or notifications on your wrist.
The hardware is deliberately simple:
Persona says it is not ambient AI, meaning it isn’t always listening and recording. That sets it apart from Bee, the wearable recorder Amazon bought in 2025. You can pair headphones if you’d rather hear replies privately.
On the software side, Persona says its agent can work with Gmail, Google Calendar, Slack, Notion, Microsoft Teams, Uber and DoorDash, among others. Depending on what you allow, it can draft and send messages, manage your calendar, make phone calls, take notes, book travel and complete purchases. Yadegari’s pitch is that the everyday utility apps on your phone will eventually fold into one assistant.
You don’t need the hardware to try it. Persona launched as a free beta that works through iMessage, so you text the assistant like a contact. Yadegari says it has attracted a few thousand beta users, and the band has already brought in five figures in preorder revenue.
The band is due to ship in December 2026. The $179 preorder price is a $40 discount from the stated regular price of $219, and it includes a knit strap, a charging dock and a USB-C cable. Persona advertises free US shipping and a one-year warranty. It hasn’t announced prices or shipping for the UK or Canada, and since the beta runs on iMessage, it’s aimed at iPhone users for now. A standalone app is in development.
An assistant that acts on your behalf needs a lot of access, and Persona knows that’s its biggest hurdle. The AI model doesn’t run on the band. Your requests go to Persona’s cloud, where data is encrypted both in transit and at rest, and you can delete your data. The company says it doesn’t sell personal information and doesn’t train its general AI models on your connected content. It also cites SOC 2 Type I certification, an industry security audit.
For purchases, Yadegari says the agent can’t see your card details. Every purchase needs your approval, and payment runs through outside services like Stripe Link, a wallet Stripe built for AI agents. Persona is also adding defenses against phishing and prompt injection, a trick where hidden instructions on a web page try to hijack an AI agent.
There are catches worth knowing. Persona’s policy says the third-party AI providers it uses may use data to improve their services, including for training, unless restrictions apply. Its terms also admit the assistant could contact the wrong person, get information wrong or make an unintended transaction. And Persona builds a long-term memory of your preferences, relationships and past tasks to work better.
Persona’s business model depends on advertising. When you ask it to research something to buy, some results will be sponsored. Yadegari says recommendations stay fair because the agent doesn’t know which items are ads. If you’re shopping for an office chair, it matches chairs to your preferences, and some of those may be paid placements.
That’s a new kind of ad deal for most people. On a search page you can usually spot a sponsored label. When an assistant speaks a short list into your ear, it’s much harder to tell, so look out for how Persona labels sponsored picks once the band ships.
Before preordering, consider what you’d actually let it do. Start with low-risk tasks in the free iMessage beta, like notes and calendar changes, before connecting email or turning on purchases. The hardware claims, from battery life to how well the microphones hear you, haven’t been tested independently yet.
The Persona Band is $179 on preorder, $40 off its stated $219 price, with free US shipping. It is expected to ship in December 2026.
No. Persona says the band activates when you press its button or flick your wrist, and it has a mute button for the microphones.
Yes. A free beta lets you use the Persona assistant through iMessage right now, and a separate app is in development.
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