This study examined the clinical utility and discriminant validity of mindreading-ⓢ, a mobile application developed to assess social cognition in young children aged 3 to 6. The app evaluates seven domains—joint attention, emotion, pretend play, perception, desire, intention, and belief—using developmentally appropriate and visually intuitive tasks. Significant differences were found between typically developing children and those with developmental delays across all domains. ROC analyses indicated high discriminative validity for joint attention (AUC = .829), desire (AUC = .810), and perception (AUC = .810), while pretend play and intention showed lower performance outcomes. Excluding these two domains, the revised total score yielded improved accuracy (AUC = .822, sensitivity = .820, specificity = .750). Age-specific cutoff scores were also identified, enhancing the tool’s clinical applicability. The app's digital format supports real-time response recording and minimizes language demands, making it suitable for early screening of social cognitive difficulties. While promising, further studies are needed to validate its use across broader neurodevelopmental conditions and to refine item quality levels.