Background <p>Early childhood is a sensitive developmental period for the acquisition of cognitive and socio-emotional skills that are strongly associated with later mental health, academic achievement, and social functioning. Children growing up in socioeconomically disadvantaged contexts are at increased risk for early emotional and behavioral difficulties, highlighting the need for accessible, scalable, and developmentally appropriate preventive interventions. Japi 2.0 is a tablet-based gaming platform designed to stimulate six interrelated cognitive and socio-emotional skills—working memory, inhibitory control, emotion recognition, social competence, empathy, and cognitive planning—through structured play in preschool settings.</p> Methods <p>We conducted a pilot cluster randomized controlled trial in low-income preschools in Santiago, Chile. Schools were randomized to either the Japi 2.0 intervention or treatment as usual. The intervention consisted of 24 individual sessions delivered over 12 weeks during regular class hours. Primary outcomes were acceptability (perceived by children, early years educators, and parents) and feasibility (recruitment, retention, attendance, intervention delivery, and data completeness). Secondary outcomes explored preliminary changes in cognitive, socio-emotional, and behavioral functioning using standardized assessments and parent- and teacher-reported measures. Exploratory analyses were conducted using multilevel models adjusted for baseline scores and clustering, based on available outcome data from randomized participants.</p> Results <p>Japi 2.0 showed high acceptability across stakeholders. Educators and parents reported that the game and the accompanying web-based dashboard were engaging, age-appropriate, easy to use, and pedagogically relevant. Children reported high levels of enjoyment and positive emotional experiences during gameplay. Feasibility indicators were satisfactory: most planned sessions were delivered as scheduled, attendance was high, and outcome data completeness was adequate. Exploratory analyses indicated improvements over time in both groups across most outcomes. Preliminary exploratory signals favoring the intervention were observed for empathy and parent-reported emotional and behavioral difficulties; however, these findings should be interpreted cautiously given the small number of clusters and exploratory nature of the analyses.</p> Conclusions <p>This pilot trial demonstrates that Japi 2.0 is a feasible and highly acceptable digital intervention for preschool children in low-income educational settings. Although efficacy findings are preliminary, results support progression to a fully powered randomized controlled trial to evaluate effectiveness and longer-term impacts on cognitive, socio-emotional, and behavioral development.</p> <p> <i>Trial registration</i> Clinical Trials NCT06420544, May 20th, 2024. https://www.clinicaltrials.gov/study/ NCT06420544.</p>