Abstract Introduction As the second leading cause of death in the EU, cancer is expected to see a 55% rise in new cases globally over the next two decades. The European Code Against Cancer (ECAC) and the EU’s Beating Cancer Plan (EBCP) provide resources for understanding and preventing cancer. The BUMPER project aims to develop a cancer prevention App to make the ECAC more accessible to the public. Objectives Understand the factors influencing the use of a cancer prevention app among users with different digital health literacy levels and to evaluate the app’s usability. Methods Mixed-methods approach was used to gather user feedback. FGDs explored user perspectives on app usage, while a cross-sectional survey assessed usability through task completion on an initial app wireframe. The pilot was conducted across seven EU countries in late 2023. Results 77 participants participated in the pilots and FGDs across seven EU countries. The average task completion time was approximately 79 seconds. Participants rated their confidence to complete the tasks at 3.96 and difficulty at 2.28 on a scale of 1 to 5. The average task pass rate was 92.11%. Qualitative findings highlighted the need for evidence-based content, user-friendly design, language accessibility, offline functionality, and data security. Participants also stressed the importance of clear instructions, regular updates, and robust tracking features. Despite some challenges, the app was generally well-received, with users appreciating its educational potential and tracking capabilities. Conclusions The BUMPER project’s pilot study demonstrated the cancer prevention App being developed as a potential tool for cancer education and awareness. Despite navigational and language challenges, the app was favorably received by a diverse user base, underscoring the need for ongoing improvements in user guidance, comprehension, and functionality to enhance accessibility. Key messages • BUMPER project’s cancer prevention app shows promise in pilot study, enhancing cancer education and awareness. • Despite challenges, the app was well-received, highlighting the need for ongoing improvements to enhance accessibility.