This document discusses the development of an app called Emotion Sense that collects sensor data from smartphones to analyze moods, behaviors, and contextual experiences. It describes initial trials with 22 users over 1 month to collect this data alongside experience sampling surveys triggered by sensor states. The work aims to understand how sensor data can help automate and personalize behavioral support. It also discusses challenges in building sensor applications and the tension between using sensors to trigger surveys while also using sensor data to quantify context. Ongoing work includes generalizing the tool and applying it to new domains.