Nowadays, e-learning technologies can be combined with mobile computing in order to create a new educational paradigm called m-learning or mobile learning. This new paradigm improves the cooperation between students and teachers, overcoming the classroom borders. This paper proposes an ubiquitous testing system (UbiSysTest) for m- Learning environments. The goal of UbiSysTest is to provide an infrastructure for creating, storing, applying and correcting academic tests. Through UbiSysTest, students can download and execute these tests by means of cell phones. This application runs off-line and only connects through Internet whenever should be required. The UbiSys- Test is being developed as part of an infrastructure named MoCoTo (Mobile Collaborative and Educational Tools).