As artificial intelligence increasingly moves into everyday devices, a new generation of wearable technology is emerging that focuses less on health metrics and more on productivity.
Startup Sandbar is one of the companies exploring this space with its AI-powered note-taking ring. The company recently announced it has raised $23 million in Series A funding, a round led by Adjacent and Kindred Ventures, as it prepares to scale production and further develop its software platform.
The funding signals growing investor interest in wearable devices designed to extend AI into daily workflows—from capturing ideas on the go to enabling more conversational interactions with digital assistants.
A Smart Ring Designed for AI-Driven Note Taking
Sandbar was founded by former Meta engineers Mina Fahmi and Kirak Hong, who set out to build a wearable focused specifically on capturing ideas and conversations quickly.
Their product, the Stream ring, offers a different approach compared to many wearable devices currently on the market. Instead of focusing on health tracking like products from Oura, the Stream ring is designed primarily as an AI-assisted productivity tool.
The device features a microphone that remains turned off by default, providing a privacy-conscious design. Users can activate recording by touching a flat, touch-sensitive panel on the ring, allowing them to capture notes or interact with an AI assistant through the companion mobile application.
Beyond note recording, the ring also supports media controls such as playing or pausing music, skipping tracks, and adjusting volume.
Interestingly, the microphone is tuned for close proximity, meaning users typically raise their hand near their face to activate voice capture—an intentional design that signals the user’s intent and reduces the chances of recording unintended background conversations.
From Stealth Development to Early User Traction
According to co-founder Mina Fahmi, the Sandbar team spent more than two years developing the Stream ring before revealing it publicly.
The product initially launched through a limited testing phase with early adopters and friends of the team. When the device was introduced more broadly last year, the response exceeded expectations.
Early demand was strong enough that the company’s first batch of pre-orders sold out quickly, prompting Sandbar to open a second batch to meet interest from new customers.
Some early users reportedly interact with the ring dozens of times each day—using it to outline presentations, capture ideas, plan trips, or organize daily tasks.
The company now plans to begin shipping the device later this summer.
Building the Software Platform Behind the Device
While the hardware has attracted attention, Sandbar says much of its focus is currently on improving the software experience surrounding the ring.
The company is working on several upgrades to its mobile and web platforms, including improvements to the user interface, faster AI response times, and expanded capabilities for managing recorded notes.
In the longer term, Sandbar hopes to build agentic workflows—systems where AI assistants can not only record notes but also take actions based on them, such as organizing tasks, summarizing conversations, or triggering follow-up steps.
Another feature currently being explored is deeper conversational interaction between users and the AI assistant. Instead of a single voice command followed by a response, Sandbar aims to support multi-step conversations that allow users to clarify or refine ideas over time.
Expanding Beyond the Ring
At present, Sandbar’s mobile application works exclusively with the Stream ring. However, the company is considering opening the app to a wider audience—even those who do not own the device.
This would allow users to continue recording notes through their phone if the ring is charging or temporarily unavailable.
The startup currently employs around 15 people, with team members who previously worked at companies including Amazon, Google, Apple, Fitbit, and Equinox.
With the new funding round, Sandbar plans to expand its engineering and machine learning teams while also hiring marketing talent as it prepares for broader product adoption.
Growing Competition in AI Note-Taking Hardware
Sandbar is entering an increasingly competitive category of devices designed to capture conversations and ideas.
Companies such as Plaud are building dedicated devices for recording meetings and automatically generating notes. Meanwhile, newer startups like Pebble are experimenting with lower-cost wearable rings, while brands such as Taya are positioning AI wearables as premium jewelry products.
According to Nico Wittenborn of Adjacent, Sandbar’s ring could stand out due to its more subtle form factor and natural interaction design.
Raising a hand to record a note may feel more intentional and private compared with devices that continuously capture conversations around the user.
Investors See Opportunity in Voice-First AI Interfaces
The company’s latest funding brings Sandbar’s total capital raised to $36 million, following a previous $13 million round led by True Ventures.
For investors, the opportunity lies not just in the wearable hardware itself but in the broader potential of voice-driven AI interfaces that can integrate seamlessly into daily workflows.
As AI continues to expand beyond screens and keyboards, devices like Sandbar’s Stream ring hint at a future where capturing ideas, interacting with assistants, and organizing information could happen more naturally through voice and wearable technology.