Educational videogames are a very effective tool in the learning process, especially for the current generation, known as the digital natives generation. Many studies have shown their benefits in different fields, using computers and mobile devices, among others. Nevertheless, we have not found in the literature any comparative research between these two platforms. Is one of the platforms more effective than the other to improve the learning process with videogames? In this paper we present the research results by using "The courtesy of Spain", a videogame created to teach its namesake classical theater play's plot by the Spanish playwright Lope de Vega. The videogame was designed to be played in a same way on computers and mobile devices. A quasi-experiment was carried out with control group and experimental group. 141 students between 9 and 11 years old from a school in the Autonomous Community of Madrid (Spain), with no previous knowledge of the play participated in the experiment. The experimental group played on a tablet, while the control group played on a computer. The researchers' first impressions were that the best results would be on tablets due to their ease of use and their great reception among young people. However, the results show statistically significant differences in favor of the computer. They reveal that: 1) the device on which an educational videogame is played is important for its effectiveness and 2) perhaps, in the field of educational videogames, the urgency of replacing the devices that is patent in the industry is not backed up by a greater effectiveness of them.