This paper presents a study on current trends in the development of cross-platform mobile applications in order to provide an overview of the actual situation of this area. The research mainly focuses on several things: first of all, it clarifies the full landscape of the cross-platform development by reviewing the most important various types of cross-platform apps, which are: Web applications, hybrid applications, interpreted applications and generated (cross-compiled) applications. Secondly, it presents basic issues for each kind of application and it performs comparative analysis to highlight the advantages and disadvantages of each type. Thirdly, it highlights the fallacies and pitfalls in various multi-platform development approaches to raise awareness about such issues and to assist in the selection of an appropriate way. In the end it presents some conclusions about cross-platform mobile app development approaches.