It has been over 100 years since the first ECG was recorded, yet it is only in the past few years that the evolution of mobile health technologies has led to a change in the way that ECGs are recorded, stored and used. In 1901, Willem Einthoven published his work on the string galvanometer,1 a device that required a person to place an arm and leg in baths of saline. The device weighed 600 pounds, occupied two rooms and required five personnel to operate it. It took several decades before the device became small enough to move to a patient's bedside and to make the 12-lead ECG become a vital part of cardiac diagnostics.

Recently, the miniaturisation of computing technology has led to the invention of small handheld ECG devices that allow a quick rhythm analysis on a patient in the clinic. These devices have been of variable quality and with limited battery life, storage and review options.

In 2007, the launch of the Apple (California, USA) iPhone transformed the smartphone market and led to a change in the way that we use our mobile phones. Current devices have more processing power than desktop computers of just 12 years ago. It is estimated that in 2014 there were around 1.75 billion smartphone users in the world and 100 000 mobile health applications available for download. …