This document discusses using technology for self-improvement through self-tracking and data collection. It covers several topics: 1) The Quantified Self movement which uses data from wearable computers and sensors to track aspects of one's life. 2) How mobile devices and sensors can track health metrics and transmit data to cloud databases and apps to provide health advice. 3) Examples of self-tracking apps that help people monitor habits like spending, productivity, and moods. 4) The potential for tracking additional behaviors and using analytics to provide real-time feedback for self-improvement.