A personal electronic device is configured to unobtrusively detect heart rate and rhythm anomalies utilizing an electrocardiogram (EKG)-based detection and monitoring method. As one example, while a user is using the personal electronic device for its intended function, such as communicating, playing music, and/or watching videos, the personal electronic device may be unobtrusively detecting and recording a user's heart rate and heart rhythm to detect anomalies. For instance, while a user is making a phone call, electrodes of the personal electronic device located in the vicinity of the earpiece and on the handset, may come into contact with a user's ear and a user's hand respectively. Thus, while the personal electronic device is being consciously used for a function other than EKG monitoring, EKG monitoring is unobtrusively occurring.