The presented study focuses on children aged from 5 to 6.5 who attend Czech kindergartens. Its purpose is to explore a potential positive impact of an educational game application on malleability of children's spatial skills through the application usage. The research was conducted as a pedagogical experiment in which the pre-test and post-test phases were carried out with the Mosaics, Puzzles and Patterns subtests of the SON-R 2.5-7 test battery, which is suitable for measuring general non-verbal intelligence in children aged 2.5-7. The game application which was created in the initial phase of the research was applied in the treatment phase to the experimental group. The results showed a statistically significant difference in the preschool children's spatial ability test scores in favour of the experimental group and confirmed statistically significant benefits of the game application in each of the measured skills. The results have clearly shown that supporting the development of spatial skills through game applications is more effective than a mere use of toys and activities recommended in the current educational guidelines for pre-school children elaborated by the Ministry of Education of the Czech Republic.