Although effective mental health treatments exist, the ability to match individuals to optimal treatment options is poor and timely assessment of response is difficult. One reason for these challenges is the lack of objective measurement of psychiatric symptoms and behaviors of daily function. Sensors and active tasks enabled by smartphones provide a low-burden, low-cost, and scalable way to capture real-world data from patients that is potentially clinically relevant and could thus augment clinical decision making to improve mental health outcomes and move the field of mental health closer to measurement-based care.