Sandbar Raises $23M Series A to Advance AI-Powered Note-Taking Ring

Sandbar, a startup founded by former Meta engineers Mina Fahmi and Kirak Hong, gained significant attention last year with the reveal of its Stream ring, a wearable device designed for note-taking. The company has now secured $23 million in Series A funding, led by Adjacent and Kindred Ventures.

Unlike health-focused wearables such as Oura, Sandbar’s smart ring is purpose-built for capturing notes, competing with devices from Plaud and Omi. The ring features a microphone that remains inactive by default but can be activated via a flat, touch-sensitive panel on the top surface. Users can tap this panel to record voice notes, interact with an AI assistant through the companion mobile app, and control media playback, including play, pause, skip, and volume adjustments.

Notably, the ring’s microphone is optimized for proximity, requiring users to lift their hand toward their face to activate note-taking functionality.

Image Credits:Sandbar /

Fahmi, who previously worked at CTRL-Labs and Magic Leap, stated that Sandbar has been developing the ring for over two years. The company emerged from stealth last year after a testing phase involving friends and early adopters.

“The response [to the launch] was much warmer than we anticipated, which is both encouraging and meaningful,” Fahmi told TechCrunch. “Many users expressed that they could see themselves wearing this device regularly.”

Fahmi noted strong early traction, with the initial batch of pre-orders selling out last year. This demand prompted Sandbar to release a second batch. Some users report using the ring more than 50 times daily for tasks such as planning presentations, trips, or meals.

The startup plans to begin shipping the smart ring this summer. Sandbar is currently refining its app experience and expanding the functionality of recorded notes. The company is developing a web platform, enhancing the user interface, and reducing model response latency. In the long term, Sandbar aims to enable agentic workflows, allowing users to take action based on their notes.

Fahmi highlighted that Sandbar is integrating conversational capabilities into its product, as many users query the AI assistant about notes they failed to complete recording.

“We believe back-and-forth conversation is essential. Unlike typical smart speakers that execute single commands, Stream excels at iterative tasks. Whether starting with a conversation or editing a note, we aim to support multi-turn interactions, such as using Claude Coding in your terminal while clarifying details via voice,” Fahmi explained.

While Sandbar’s phone app currently supports only the Stream ring, the company is considering making it available to non-users. The app can function independently to take notes if the ring is charging or misplaced.

Sandbar employs 15 people, many of whom have backgrounds at Amazon, Fitbit, Equinox, Google, and Apple. With the new funding, the company plans to double its software and machine learning teams and hire marketing staff.

The market for note-taking hardware is expanding. Companies like Plaud are producing meeting-focused devices, while Pebble plans to launch an affordable $75 ring this year. Meanwhile, startups like Taya are targeting a broader audience by designing premium jewelry-style devices.

Adjacent’s Nico Wittenborn, who previously invested in voice-focused startups like Blinkist while at Insight Venture Partners, believes Sandbar’s Stream offers a superior form factor compared to other note-taking devices. He argues that lifting your hand to take a note signals a private use case, distinguishing it from devices that might inadvertently record surrounding conversations.

Wittenborn also noted that much of the current hardware targets only “tech enthusiasts,” whereas Sandbar’s design is better suited for widespread adoption.

Sandbar previously raised $13 million from True Ventures last November. To date, the company has secured $36 million in total funding.