**4.2 Back-end**

To ensure that the app can be deployed to both Android and iOS, Cordova PhoneGap [21] was used to develop the mHealth passport. PhoneGap uses web technologies such as HTML, CSS, and JavaScript in addition to Frameworks for navigations and layouts. For this passport, Framework 7 [22] is incorporated into the app to ensure a consistent layout/style across both Android and iOS. The language and dialogue used in the app is simple so that it can be understood by nonmedical persons. All graphs are developed using the Highcharts.js framework [23]. This section will discuss the validation of content and dialogue within the application before discussing the data that can be recorded via the passport app.
