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Sleep

sleep-trackers

02Excellent
11/12
Quality Score
Apple

Apple Watch Series 9

$399$399/unit
smartwatchhealth trackingsleep stagesFDA cleared

The Apple Watch Series 9 features some of the most accurate heart rate and motion sensors on the market. Its sleep stage tracking has been rigorously validated against PSG, often outperforming dedicated sleep trackers in identifying Deep and REM cycles.

Score BreakdownStrong Evidence
Purity
Evidence
Transparency
Value
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Quality & Materials

Available in 100% recycled aluminum or stainless steel. The back crystal is sapphire or ion-X glass, ensuring high-quality sensor transmission.

Evidence & Testing

Apple's sleep tracking validation study involved over 1,000 participants and demonstrated high sensitivity in detecting sleep stages compared to clinical PSG.

Brand Transparency

Apple publishes detailed 'Healthcare' white papers explaining the methodology and clinical validation behind their heart and sleep algorithms.

Value Assessment

High upfront cost ($399), but no mandatory monthly subscription to access your data, which gives it better long-term value than Whoop or Oura.

Why Not Alternatives?

The Apple Watch offers superior sensor accuracy compared to Fitbit or Garmin for sleep staging. While battery life is shorter than Oura, the breadth of health metrics (ECG, Blood Oxygen, AFib history) is unmatched.

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