In this paper we present a mobile application for self-assessment. The work describes the main features of the application and focuses on its acceptance by students and the increase on their learning, through its usage in real testing settings. The application supports the retrieval of questions based on a number of criteria and it was evaluated with the aid of students who self-assessed their knowledge prior to in-class pencil and paper tests. An improvement in the performance of students who actively engaged with the system has been observed. [This work has been partially supported by a grant from Stavros Niarchos Foundation (SNF). For the complete proceedings, see ED579190.]