The Study Watch is an investigational wrist worn wearable device made with biocompatible contact materials containing various sensors capable of continuous recording of physiological, activity, and environmental data.

The Vivalink ECG Patch is a continuously recording ECG monitor and will be used as a reference device for measuring participants' pulse rate, pulse rate variability, and pulse rate coverage. The Vivalink ECG Patch is a medical device manufactured by VivaLNK Inc. and has been cleared by the FDA.

Modus StepWatch 4 is an ankle-worn wearable medical device, and will be used as a reference device for measuring participants' ambulatory time and daily step count. The Modus StepWatch 4 is FDA listed.

To evaluate the accuracy of the Verily Clinical Study Watch's ability to measure pulse rate when wearer is at rest during unsupervised free-living conditions. Pulse rate measurements will be compared against heart rate output from the reference device (FDA cleared ECG patch).

To evaluate the accuracy of the Verily Clinical Study Watch's ability to detect movement (rest vs not rest) during supervised conditions. Movement detection will be compared against virtual supervised observer-reference labels of rest vs not rest.

To evaluate the accuracy of the Verily Clinical Study Watch's ability to detect movement (rest vs not rest) during supervised conditions. Movement detection will be compared against virtual supervised observer-reference labels of rest vs not rest.