The present invention relates to a non-invasive cardiac monitoring device that records cardiac data to infer physiological characteristics of a human, such as cardiac arrhythmia. Some embodiments of the invention allow for long-term monitoring of physiological signals. Further embodiments allow for processing of the detected cardiac rhythm signals partially on the wearable cardiac monitor device, and partially on a remote computing system. Some embodiments include a wearable cardiac monitor device for long-term adhesion to a mammal for prolonged detection of cardiac rhythm signals.