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Budget smart ring · Ring · by Circular
Circular Ring Slim
An ultra-thin 2.2mm ring with haptic alarms and an AI assistant — ambitious features undercut by accuracy and stability problems.
2024Circular Ring Slim
Mid-cycle1 yr 9 mo old
API access: No Raw data access: No Open source: No public repo
Clinical value
22/100
Inaccurate per reviewers
Empowerment
38/100
No subscription, buggy app
Everyday value
48/100
Thin, but scratch-prone
An extremely thin (2.2mm) budget smart ring with a haptic vibration motor for smart alarms and the Kira+ AI conversational wellness assistant. Despite the appealing form factor, reviewers report inaccurate temperature and sleep staging, scratch-prone hardware and erratic battery.
What it measures
Sleep stages, heart rate, temperature and activity with haptic alarms and an AI assistant — though reviewers question the accuracy of several metrics.
Regulatory status
Consumer wellness device; no clearance.
Validation & accuracy
Reviewers report highly inaccurate temperature readings (drops well below normal), missed deep-sleep phases, and erratic ~2-day battery — incoherent for serious longitudinal tracking.
Data control & export
Raw data: restricted — app-based with no open export; syncing failures have reportedly wiped recorded sessions.
Wearability & battery
A standout 2.2mm-thin ring with haptic alarms, but it is highly scratch-prone and battery life is inconsistent.
Cost & access
Budget pricing with no mandatory subscription.
Who it serves
Buyers wanting the thinnest ring and AI/haptic features at a low price.
Who is left out or burdened
Accuracy and stability problems; scratch-prone; buggy app; data loss reports.
✓ Strengths
- Ultra-thin 2.2mm profile
- Haptic vibration smart alarms
- Kira+ AI wellness assistant
- No subscription
✕ Weaknesses
- Inaccurate temperature and sleep staging
- Scratch-prone hardware
- Erratic battery, buggy app
- Reported data loss
22
Why this clinical score. Reported inaccuracy in temperature and sleep staging undercuts trust, keeping the clinical score very low.
38
Why this empowerment score. No subscription helps, but a buggy app, no open export, and data-loss reports hold empowerment low.
48
Why this everyday score. The thin profile and haptic alarms are appealing, but scratch-proneness and erratic battery drag everyday value down.
Latest news
Reviews & coverage
Reviewers praise the remarkably thin design, haptic alarms and AI assistant in concept, but report serious problems: inaccurate temperature and sleep staging, scratch-prone hardware, erratic battery and app sync failures that can wipe data. The verdict is that the data is hard to trust for longitudinal use.
Summary is a draft synthesis of public coverage, not an endorsement. Links open a search of each outlet.
Reddit communities
Independent user communities where this device (or its category) is discussed.
Get it · manuals & support
Draft profile · public-source review, June 2026 · scores describe direction and degree, not buying advice. News, links, and prices change — verify with the manufacturer. Image is representative.