DeltaDroid: Dynamic Delivery Testing in Android

Android is a highly fragmented platform with a diverse set of devices and users. To support the deployment of apps in such a heterogeneous setting, Android has introduced dynamic delivery —a new model of software deployment in which optional, device- or user-specific functionalities of an app, called Dynamic Feature Modules (DFMs) , can be installed, as needed, after the app’s initial installation. This model of app deployment, however, has exacerbated the challenges of properly testing Android apps. In this article, we first describe the results of an extensive study in which we formalized a defect model representing the various conditions under which DFM installations may fail. We then present DeltaDroid —a tool aimed at assisting the developers with validating dynamic delivery behavior in their apps by augmenting their existing test suite. Our experimental evaluation using real-world apps corroborates DeltaDroid ’s ability to detect many crashes and unexpected behaviors that the existing automated testing tools cannot reveal.