The traditional or the native way to develop mobile applications is to use Java for Android and Objective-c or Swift for iOS. The native way is favored by many since the code and the functionality is optimized for the platform. An- other way to develop mobile applications is to do it the non-native way, with a programming language or technique not made for the platform. This approach has for long been frowned upon due the limited hardware access and perfor- mance loss. React Native and NativeScript offers mobile application develop- ment in a non-native way said full access to the native platforms API using JavaScript all from a single code base. The aim of this thesis has been to de- velop and compare four proof of concept applications of which two are devel- oped natively for Android and iOS and the other are developed using the non- native React Native and NativeScript. The comparison is based on three as- pects: accessing the device’s native hardware and APIs based on what the com- pany Dewire requires from mobile applications, the performance difference on the respective platform and code reusability cross platform. There is no big dif- ference between React Native and NativeScript when comparing native access and everything that was accessible on the native implementation was accessible on the non-native implementation. Based on the performance measurements, React Native falls behind NativeScript. NativeScript handles long lists better than React Native. Lastly a discussion is presented regarding code reusability when developing non-native applications along with some experienced best practices when doing so.

With rapid technology growth and a rising disabled and aging population, mobile appaccessibility is vital. Stricter accessibility laws, especially in the public sector, highlight thisemphasis. However, despite this, the body of research focusing on software practitioners’perspectives, especially concerning cross-platform development, is lacking. In this qualitativecase study, six software practitioners at the Swedish Social Insurance Agency(Försäkringskassan) were interviewed about their experience during a migration betweenmobile development technologies, with a focus on enhancing mobile application accessibility.It explores their attitude to cross-platform development, their challenges with NativeScript, across-platform framework, and preferences for native technology. To further understand theiracceptance of native technology and their rejection of cross-platform technology in thiscontext, an extension of the Technology Acceptance Model (TAM2) was used. Respondents emphasized the legal and ethical obligations for accessibility in the publicsector, with evolving standards necessitating the selection of the most appropriate technologyfor the task. Prioritizing accessibility early on in public sector app development helps avoidadditional expenses later on. It's also possible that private sector apps may be required to shifttowards greater inclusivity in the future. The team successfully addressed previous accessibility issues using native technology, whichinfluenced the organization to migrate. Moreover, respondents believed that nativetechnology enhances professional image, especially as the industry favors it over unknowncross-platform frameworks. They perceived that cross-platform frameworks might lackthorough documentation and community support, making it more difficult to manage andimplement accessibility. Additionally, respondents are alarmed by the uncertain nature ofcross-platform technology, which can result in outdated frameworks and unworkablecodebases. It's crucial to consider the duration of the project, its accessibility needs, and theavailable support for implementing accessibility when deciding on mobile developmenttechnologies. These findings are valuable for various stakeholders, such as consultants,researchers and policy-makers.