This document discusses the rise of wearable health technologies and quantified self-tracking. It notes that healthcare is now an information problem rather than a science problem. It then discusses the growing elderly population and rise of chronic diseases. Common risk factors like smoking, obesity, and inactivity are also discussed. The document summarizes tracking trends and the quantified self movement. It provides examples of emerging personal health tools like glucose monitors and DNA screening. It concludes with the author's views that digitalization will transform medicine by lowering costs and improving outcomes through precision medicine approaches.