In the United States alone, 38 million people start their day by eagerly fastening a device to their wrist that is not worn for the purpose of fashion or keeping time. It is a fitness tracker and these little gadgets have swept the nation. Why? Because people love having instant access to their performance, activities and goals. They enjoy tracking their progress throughout the day. They are addicted to the gratifying notifications of success, and the social aspects of competing with friends, family members, and coworkers.