Apple’s Vitals app, explained
What the built-in Vitals app shows overnight, and how that differs from Early Signal.
Last reviewed 2026-09-24 · Sources · Editorial policy
01What Vitals shows
Apple’s support article lists overnight heart rate, respiratory rate, wrist temperature, blood oxygen, and sleep duration. You wear the watch to sleep so it can establish a typical range—Apple says about seven nights. Outliers are marked against that personal range, not against a population chart.
02When it notifies you
By default, Vitals can notify you when multiple overnight metrics are outside your typical range, and it offers context for factors that can be involved. That is Apple’s own view of the night. It is not a diagnosis.
03Where Early Signal is different
Early Signal runs on the iPhone, on device, from Health samples you already have. It treats wrist temperature and breathing as lead signals, HRV and resting heart rate as support, and sleep as context. Status is Typical, Slightly off, or Off from usual, with alerts capped. It does not replace Vitals. It is a wellness tool: it does not diagnose or treat disease, and it is not medical advice.
Guide FAQ
01Do I need both?
02Does Vitals include HRV?
Sources
Public documentation cited as context—not as clinical validation of Early Signal.
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How it compares
Factual comparisons. No prices or ratings.
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