Mobile applications and mobile devices are becoming more and more pervasive in our everyday life supporting a wide range of activities in different contexts. An “app” is a highly event-oriented software thought to react to a set of inputs typical of the mobile world. Furthermore, mobile devices themselves are characterized by a mixture of attributes that can affect in many ways how an app’s graphical user interface (GUI) is displayed. This highlights the need to have applications that have been tested extensively and from different points of view. Despite these factors, visual GUI testing (VGT) is not a common activity. The existing tools introduce a collection of different approaches to this activity, with specific testing goals and suffering of well-known weaknesses.