HRV Watch: Stress & Recovery

HRV Watch shows your Apple Health heart rate variability on iPhone and Apple Watch. Follow your history, compare sleep and mindfulness readings separately, and see changes against your own personal baseline. Understand your readings - Daily values, a personal range and the number of readings behind each day - Separate views for all readings, sleep and mindfulness - Tap a chart point to explore the day and its individual readings - HRV basics, chart explanations, methods and sources in the app - Home Screen and Lock Screen widgets, Apple Watch complications, and configurable notifications SDNN and RMSSD stay separate The app supports SDNN and, on iOS 27 or watchOS 27, native RMSSD readings when available in Apple Health. Each metric has its own history and baseline. SDNN is not converted into RMSSD. Missing readings are not replaced with invented values. HRV measures variation in the time between heartbeats. Measurement duration and conditions affect the values. One high or low reading does not establish stress, recovery or illness. Context, not a diagnosis Sleep, resting heart rate, respiratory rate, wrist temperature and workouts provide context when those data are available. The app's readiness estimate uses HRV and resting heart rate relative to your baseline. It is not Apple's readiness score or a medical assessment. Without enough data, the estimate stays unavailable. Getting started Allow read access to the relevant Apple Health data. The app displays existing measurements; it does not measure HRV itself or replace a sensor. Requires iOS 18 and watchOS 11 or later. RMSSD additionally requires iOS 27 or watchOS 27 and native readings in Health; not every Apple Watch provides them. Optional AI explanations If you enable AI data sharing, selected health and workout values are sent to OpenAI to generate explanations. Baselines and readiness estimates are calculated by the app, not by AI. The Watch's day details use local context without an automatic AI request. Medical disclaimer HRV Watch is a tool for personal trends, not medical diagnosis or treatment. Seek qualified medical advice for health questions and before medical decisions. Scientific references available in the app: - HRV standards: https://pubmed.ncbi.nlm.nih.gov/8598068/ - HRV review: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5624990/ - AHA heart rate guidance: https://www.heart.org/en/healthy-living/fitness/fitness-basics/target-heart-rates Terms: https://www.apple.com/legal/internet-services/itunes/dev/stdeula/