Accurate recognition and tracking of human activities is an important goal of ubiquitous computing. The goal is to create a personal portable device that can determine a user’s activity and make it available to their context-aware applications.   In this talk, Gaetano Borriello and Tanzeem Choudhury present their prototype system that consists of a multi-modal wearable sensing device that communicates wirelessly to any commodity Bluetooth device and can be easily incorporated into a cell phone or a wristwatch. From the Series:CSE Colloquia - 2005