Testing user interfaces (UIs) is a challenging task. Ideally, every sequence of UI elements should be tested to guarantee that the application works correctly. This is, however, unfeasible due to the number of UI elements in an application. A better approach is to limit the evaluation to UI elements that affect a specific functionality. In this paper I present a novel technique to identify the relation between UI elements using the statically extracted data flows. I also present a method to refine these relations using dynamic analysis, in order to ensure that relations extracted from unreachable data flows are removed. Using these relations it is possible to more efficiently test a functionality. Finally, I present an approach to evaluate how these UI-aware data flows can be used as an heuristic to measure test coverage.