This article describes the conceptual development of a learning app, “Representations”, developed for preschool children (4–5 years of age). In this article we analyze how the app supported the development of logical reasoning via a variety of decoding, encoding, conditionals and debugging activities, which were supported in the game play by the children’s own user generated content (UGC). Research such as this is important as logical reasoning in young children correlates positively with later mathematics achievement. The learning app is used within a broader program, which also included a range of off-device learning. Data indicates the success of our design and implementation in terms of children’s engagement with the app and in terms of their early learning of important logical reasoning concepts.