Classrooms are increasingly equipped with information and communication technology and especially interactive mobile devices. However, the latest studies show that their use by teachers is still very limited because of a lack of resources and applications adapted to an educational use. Indeed, there seems to be a shortage of mobile learning practitioners due to the time required for these tools' apprehension. Likewise, studies show real needs to expand the variety of applications, resources and activities available on these mobile devices, in order to make them more suited to the teachers' pedagogic objectives. Concurrently, new ways of using mobile devices for education are arising. Among those directions of use, research conducted on Mobile Learning Games (MLGs) seems particularly promising. In this paper, we propose to identify several MLGs, from the most referenced scientific assessments, that have been carried out in educational context, in order to determine their common features and impact on learners, and to identify challenges in terms of design, storyboarding and student monitoring. Thus, we can discuss how far research on MLGs has gone in terms of pedagogical effectiveness and whether there are still challenges that teachers will be facing regarding the design and execution of MLGs. At this level, we try to define the main characteristics of the analysed MLGs, and identify the recurring problems that occur when teachers use them. First, this will allow us to establish several guidelines for designing MLGs. Secondly, in order to diminish the constraints of use, we discuss new ways of implementing MLGs. Furthermore, we propose a global MLGs model, capable of capitalizing the identified main characteristics and overcoming the recurring problems at the same time. Finally, we discuss the possibility of implementing this model through an authoring environment.