The aim of this thesis is a theoretical research of the student model in intelligent tutoring systems (ITS) and a practical realisation of the concepts on Android
OS, due to the rapid growth of the mobile segment and a lack of ITS in the mobile field. Various approaches in creating a student model and learning styles
are presented. The second part of the thesis introduces the implementation of a simple ITS, where the student model is built using fuzzy logic, stereotypes and an overlay model. In the present case, the learning domain is represented by basic operations with fractions. The application provides personalised content based on the current state of the learner model. In addition, it offers personalised assistance, and a feedback for optimal learning.