Mobile apps (or apps) are software applications developed to run on mobile devices such as smartphones and tablets, among other devices. The number of apps has grown tremendously since Apple opened the first app store in 2008. For example, in March of 2009 the Google Play app store (formerly known as Android Market) had only 2,300 apps, and by mid of 2013 there were more than 800,000 apps. Given the accelerated rate of growth in the number of apps, new software engineering challenges have emerged in order to help ease the software development practices of app developers. In this thesis we examine three examples of these challenges, namely code reuse in mobile apps, app ratings, and the use of ad libraries within apps. We carry out our case studies on thousands of Android apps from the Google Play market. We find that code reuse in mobile apps is considerably higher than in desktop/server apps. However, identical copies of mobile apps are rare. We find that the current ratings system is not able to capture the dynamics of the evolving nature of apps. Thus, we were able to show the need for a more elaborate rating system for the apps. Finally, we observe that a considerable number of free-to-download apps are dependant on ads for their revenue. Our findings suggest that "ad maintenance" is a tough challenge that developers of mobile apps have to face. / Thesis (Master, Computing) -- Queen's University, 2013-08-04 22:03:54.577