Background: Diagnosis delay in children and adolescents with cancer is a public health problem in Peru that leads to high rates of advanced disease and mortality. We aimed to assess the implementation feasibility and potential utility of ONCOpeds®, a mobile application that provides consultations with pediatric oncologists, in reducing the latency to diagnosis (LD) and referral time (RT) among children and adolescents in Peru diagnosed with cancer. Material and Methods: A prospective pilot study was conducted in the region of Callao between November 2017 and April 2018. Primary and secondary care providers were trained on the use of ONCOpeds in five educational sessions. Patients younger than 18 years who resided in Callao and were diagnosed with cancer at four pediatric cancer units in Lima were analyzed by referral type: ONCOpeds facilitated or conventional. Results: ONCOpeds was successfully installed in the smartphones of 78 primary and secondary care providers of Callao. During the study period, 23 new cases of cancer in children and adolescents from the region were diagnosed. Ten patients received ONCOpeds-facilitated referrals and 13 received conventional referrals. The RT decreased among those who received ONCOpeds-facilitated referrals by 66% (P = 0.02); however, the LD did not significantly decrease with the use of ONCOpeds. Conclusions: The implementation of ONCOpeds was found to be feasible in this pilot study, having a potential utility in improving early diagnosis and referral in children and adolescents newly diagnosed with cancer. Directions for future research include multicenter studies with a larger population to further test the application's effectiveness.