## 5 Mobile Application for ECG Interpretation
### Appraisal of the Existing ECG Mobile Application  
There is an upraise in the use of mobile smartphones since the beginning of the 21 st century, and reports from surveys have revealed that over 100,000 mobile health apps and 400 wearable activity monitors exist on mobile stores (iTunes and Google Play) [21]. It was also reported that 62% of mobile phone owners in the United States use their phones to access health information about diseases and health conditions [21]. In recent years, there has been a notable upsurge in the number of mobile phone applications focusing on  
Figure 8: A generic design architecture of an ECG mobile application. the management of cardiovascular diseases, some of which are based on measuring and analyzing ECG traces of patients. This section focuses on the appraisal of a representative sample of selected mobile applications proposed in the literature and those available on mobile stores for the acquisition and interpretation of ECG signals. This study identifies key features of mobile applications in the effective management and monitoring of heart disease patients via ECG interpretation. The features include development platform, air interface connection, measured parameters, server upload capability, server type, market availability and security of patient data. Table 2 presents the summary of the appraisal of the existing ECG mobile applications. It can be observed that the majority of the mobile applications use Bluetooth as a connection medium for raw ECG signal acquisition, except for ALiveCore's CardiaMobile, IMED Kft's Cardiac and Ardas' Cardiolyse, which use ultrasound, Wi-Fi and OTG USB connectors as the acquisition mediums. Similarly, most of the apps are android-based, with the exception of CardiaMobile, which is a cross-platform, and Cardiac for Windows and Android. Due to the computational capability of mobile smartphones, mobile applications for ECG measure a limited number of parameters of ECG traces, heart rate and QRS cutting across all identified apps both on app stores and published literature. Some Mobile Apps, especially the ones presented in published journals, measure some other patient non-ECG parameters that could aid heart disease diagnoses such as temperature [122], BPM [20; 24] and blood pressure [122]. It is also observed that some of the mobile apps include GPS location timestamps in the captured data so that remotely monitored patients can be timely rescued in an emergency situation [24; 122]. It is also noticed that few mobile apps are used to detect heart rate abnormalities directly. Majority of them only preprocess the ECG signals and send to the cloud for in-depth analysis to detect heartbeat abnormalities. This might be due to the complex property of ECG signal which requires sophisticated algorithms that mobile devices cannot handle. Nevertheless, CardiaMobile, Cardiac and TouchECG possess the functionality to detect certain heartbeat abnormalities such as limited types of arrhythmias, sinus rhythm and heart attack. In terms of the security of patient data, the majority of the mobile apps available did not provide any encryption techniques for protecting sensitive health-related data of users from unsolicited and unverified access. The few that provide this security functionality require premium subscriptions which many users may not be able to afford.