RecruitingDiagnostic testDetection of Atrial Fibrillation Using PPG From Smartphone CamerasThe protocol is designed to enroll patients from at least 3 diverse clinical sites with smartphones who are being evaluated for the presence or absence of atrial fibrillation (AF) using the Heart Rhythm Software algorithm running on their smartphones. Algorithm output will be compared to a gold standard of 12-lead ECG recorded with a simultaneous PPG measurement.