Context. Both smartphones and PC games are increasingly commonplace nowadays. There are more and more people who own smartphones and – at the same time – like playing video games. Since the smartphones are becoming widely affordable and offer more and more advanced features (such as multi-touch screens, a variety of sensors, vibration feedback, and others), it is justifiable to study their potential in new application areas. The aim of this thesis is to adapt the smartphone for the use as a game controller in PC racing games and evaluate this solution taking into account such aspects as race results and user experience. Objectives. To this end, two applications were developed - a game controller application for Android‑based smartphones (i.e. the client application) and a PC server application. The applications support a selected open-source PC racing game called SuperTuxKart. The evaluation of the smartphone encompasses both race results (whether the smartphone enables players to achieve comparable results to the keyboard – a standard game controller) and user experience (whether this game controller may be satisfying to players). Methods. An experiment was conducted where 20 participants controlled the SuperTuxKart game using first the smartphone, and then the keyboard or vice versa. The experiment was followed by a questionnaire-based survey of the user experience. Results. The experiment results indicate that the smartphone may achieve results which are comparable to those achieved by the keyboard. The race times corresponding to the smartphone were somewhat longer than those obtained with the keyboard, but the average relative difference was below 18%. The questionnaire results show that more than half of the participants enjoyed the smartphone more than the keyboard, despite the fact that the smartphone turned out to be a more challenging game controller for many players and did not provide so good control of the racing game as the keyboard. Conclusions. Overall, this study shows that the smartphone has a potential to be a suitable, satisfying and enjoyable controller for PC racing games.