Many smartwatches and smartphones can record single lead electrocardiograms. If technically clean, such recordings are diagnostic for atrial fibrillation (AF). The implications of screening-detected AF are incompletely understood. Clinically diagnosed AF typically requires initiation of oral anticoagulation. In recent studies on screening-detected AF, oral anticoagulation did not significantly reduce the risk of stroke. Pending tailored guideline recommendations for screening-detected AF, it appears that unlike for clinical AF, in general anticoagulation should not be started routinely.