Circular

• Circular Ring 2

  The Circular Ring 2, unveiled at CES 2025, is a thin smart ring built around FDA-cleared ECG and AFib (atrial fibrillation) detection, extending the device toward clinical heart monitoring. It tracks sleep, recovery, heart rate, and activity, offers around 8 days of battery life with wireless charging, and requires no subscription to access core data. Circular replaced plastic sizing kits with a measurement approach of its own, and began shipping the ring to crowdfunding backers in mid-2025 after an extended development cycle.

• Kira+ AI assistant

  Kira+ is Circular's AI-driven wellness assistant, layered on top of the ring's sensor data inside the companion app. It interprets sleep, recovery, and heart-health metrics to deliver personalized, conversational guidance and holistic well-being insights rather than raw numbers alone. By coupling its hardware with an AI coaching layer, Circular aims to differentiate from larger rivals on software-driven personalization, positioning Kira+ as the interpretive front end to the data the Ring 2 collects throughout the day and night.

Most recent patents

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