This paper describes a heart attack self-test application for a mobile phone which allows potential victims of a heart attack to quickly assess whether they are having a heart attack without the intervention of a medical specialist. Heart attacks can occur anytime, anyplace. Using pervasive technology such as a mobile phone and a small wearable ECG sensor it is possible to collect the user’s symptoms and to detect the onset of a heart attack by analysing the ECG recordings. If the application assesses that the user is at risk, it will urge the user to call the emergency service immediately. If the user has a cardiac arrest the application will automatically determine the current location of the user and alert the ambulance services and others to the person’s location.