Sandbar, a startup founded by former Meta employees Mina Fahmi and Kirak Hong, generated significant buzz last year with the debut of its note-taking wearable, the Stream ring. The company has now secured $23 million in a Series A funding round, with Adjacent and Kindred Ventures leading the investment. This smart ring is designed specifically for note-taking, aligning it with products from companies like Plaud or Omi, rather than health-tracking devices such as those from Oura. The ring features a microphone that remains off by default but can be activated using a flat, touch-sensitive panel on its top surface. By holding this panel, users can record notes, interact with an AI assistant through a companion phone app, and manage media playback—including play, pause, track skipping, and volume control. An important design aspect is that the microphone is tuned for proximity, requiring the user to lift their hand toward their face to effectively capture audio notes.

Fahmi, whose background includes roles at startups like CTRL-Labs and Magic Leap, noted that Sandbar has been developing the ring for more than two years. The company emerged from stealth mode last year after conducting a testing phase with friends and early adopters. “A lot of people said they could see themselves wearing this,” he remarked.

The startup is encouraged by early user engagement, with its first batch of pre-orders selling out last year. This demand prompted Sandbar to open a second pre-order batch. According to Fahmi, some users interact with the ring over 50 times daily for activities such as planning presentations, trips, or meals. Shipments of the smart ring are scheduled to begin this summer. Currently, Sandbar is focused on refining its app experience and expanding the functionality of recorded notes. Efforts include developing a web platform, enhancing the user interface, and reducing latency in AI model responses. Long-term goals involve enabling agentic workflows that allow users to take actionable steps directly from their notes. Fahmi highlighted that the company is working to incorporate conversational exchanges into the product, as many users query the AI assistant about incomplete notes. “Something that we think is necessary is back and forth conversation. Unlike a lot of experiences where you just say one command and it’s either transcribed or acted upon, like, via a smart speaker, Stream is really good at iterative tasks which begin, maybe in conversation or editing a note, but hopefully expand to multi-turn conversations, where you’re Claude Coding in your terminal and you are clarifying things [via voice],” he explained.

While Sandbar’s phone app currently requires the Stream ring, the company is considering offering access to users without the hardware. The app can function independently for note-taking if the ring is charging or misplaced. Sandbar employs 15 people, with team members having previously worked at companies such as Amazon, Fitbit, Equinox, Google, and Apple. The new funding will support doubling the size of its software and machine learning teams, along with hiring marketing personnel.

The market for hardware note-taking devices is expanding. Companies like Plaud create devices for meeting notes, while Pebble aims to launch an affordable $75 ring this year. Other startups, such as Taya, are adopting a premium, jewelry-inspired design to appeal to a broader audience. Nico Wittenborn of Adjacent brings experience investing in voice-focused startups, having previously backed Blinkist, a service that summarizes books, during his tenure at Insight Venture Partners. He believes Sandbar’s Stream offers a superior form factor compared to other note-taking devices, and the gesture of raising one’s hand to record reinforces a private use case, unlike devices that might capture surrounding conversations. Wittenborn also observes that some existing hardware caters predominantly to “tech bros,” whereas Sandbar’s design has the potential for wider adoption.

Sandbar previously raised $13 million from True Ventures last November, bringing its total funding to date to $36 million.