This is a secured app for the VAPing Observational Research Study (VAPORS). This app will track e-cigarette users and e-cigarette non-users (via a monthly questionnaire) to longitudinally determine the impact of e-cig use on a variety of health endpoints, including oral health, lung health, cardiovascular health, and physical activity. Each individual will be followed for 2 years, and participate in 3 yearly health assessments.