Described herein are apparatuses (e.g., devices, systems, software), and methods for monitoring the cardiac health of a patient. The apparatuses and methods may include a smartphone or hand held computing device having an accelerometer. The apparatus may also include a device with a plurality of electrodes integral with or attached to the smartphone. The devices can be placed on a patients chest to measure electrical signals and vibrations on the chest caused by the heartbeat. The measurements can generate a seismocardiogram (SCG) and in some variations an electrocardiogram (ECG). The apparatuses and methods can analyze the data in the SCG to produce a measure of the cardiac function. Changes in such measures can provide an early warning for potential cardiac problems and signal the need for the patient to seek treatment prior to a fatal cardiac event.