Sandbar’s Stream Ring Secures $23M Series A Funding to Advance Wearable AI Interface
Sandbar, a New York-based interface company, has raised $23 million in a Series A funding round led by Adjacent and Kindred Ventures, bringing the company’s total funding to $36 million. [CityBiz] This investment follows a $10 million seed round led by True Ventures in early 2025 and a $3 million pre-seed round backed by Upfront Ventures and Betaworks in early 2024. [CityBiz] The funding will be used to accelerate hiring and development of Stream, Sandbar’s first product, ahead of its planned summer 2026 launch.
Introducing Stream: A Conversational Interface
Stream is a voice-activated smart ring designed as a private conversational interface. [TechCrunch] It combines a hardware ring with AI-powered software, allowing users to capture ideas, organize notes, and retrieve information without relying on a smartphone. [CityBiz] The ring features a touchpad, a personal microphone, and haptic feedback.
Privacy and User Control
Unlike many voice assistants, Stream prioritizes user privacy. The microphone is off by default and is activated only when the user holds the touch panel. [TechCrunch] This deliberate activation method ensures that audio is only captured when the user intends, offering a more controlled experience. Sandbar emphasizes that Stream is designed “without an identity of its own,” focusing on remembering user input and responding to requests without continuous listening. [CityBiz]
From Neural Interfaces to AI Hardware
Sandbar was founded by Mina Fahmi and Kirak Hong, who previously collaborated at CTRL-labs, a neural interface startup acquired by Meta in 2019. [TechCrunch] Their experience at CTRL-labs focused on bridging the gap between human intent and action, including work on Meta’s neural wristband projects. [CityBiz] The team currently comprises around 15 people with backgrounds in consumer technology and product design, including experience with devices like the iPhone, Vision Pro, Fitbit, and Kindle. [CityBiz] Recent hires include Sam Bowen as Vice President of Hardware and Brooke Travis as Vice President of Marketing.
A Growing Market for AI Wearables
Sandbar enters a competitive market for AI-powered wearables. [TechCrunch] While some companies focus on health tracking, like Oura, Sandbar differentiates itself by concentrating on voice interaction and note-taking. [TechCrunch] Other companies are exploring similar devices, including rings and pins, designed for AI interaction. [TechCrunch]
Looking Ahead
Sandbar plans to launch a closed beta program in the coming months to refine the Stream software experience. [TechCrunch] A new feature, “Inner Voice,” will allow the system to respond using a personalized voice. [TechCrunch] The first batch of pre-orders sold out quickly, indicating strong initial demand. [TechCrunch] With the new funding secured, Sandbar aims to establish wearable AI interfaces as a natural and efficient way to interact with technology.