UI Testing Cross-Device Applications

The increasing number of devices available to a user has prompted the research community to explore how these can be used in combination. Frameworks and toolkits have been proposed to facilitate the design and implementation of these cross-device applications. Still, implementing cross-device applications remains complex because of the fragmentation of the user interface and logic across devices and the flexibility required to adapt to different combinations of devices. Testing in particular has been identified as a critical challenge. To address these issues, we introduce XD-Testing, a library that provides explicit and implicit device selectors, device templates and scenarios, as well as a visualiser for application screenshots. In a case study, we demonstrate how we used the library to author human-readable tests for a cross-device gallery that verify if a UI distributes correctly and if it works as expected despite being distributed.