Depression affects an astounding 300 million people worldwide and one of society’s biggest problems – yet it is poorly understood. In 2018, UCLA launched the Depression Grand Challenge (DGC) with the ambitious goal of cutting in half the worldwide burden of depression by 2050. New diagnostic and treatment methods are being explored, including mHealth. The DGC, in a partnership with Apple Inc., launched a major study to provide greater insights into how we diagnose and treat anxiety and depression. Using devices connected to a smartphone/smartwatch, we are obtaining objective measures around sleep, physical activity, heartrate and daily routines to illuminate the relationship between these factors and symptoms of depression and anxiety. This joint effort has the very real potential to transform behavioral health research and clinical care by enabling healthcare providers to note warning signs before severe mental health crises occur. The study is also an important step toward greater understanding of the different types of depression, and which treatments work best for each. As part of this effort, we are helping with subject recruitment, as well as coordinating secure sensor data collection and integrated analysis.