Cosmic rays are high-energy particles originating from space that continuously bombard the Earth. However, their detection typically requires expensive and specialized equipment, rendering such observations largely inaccessible to the general public without expert support. In recent years, smartphone-based methods for detecting cosmic rays and ionizing radiation have gained attention as powerful tools for citizen science and science communication. This paper introduces"SORAMAME", a smartphone application that detects ionizing radiation using CMOS image sensors and visualizes particle events in real time. Designed with a focus on accessibility and educational use, the app enables anyone to participate in global cosmic ray observations without requiring any external hardware. We describe the architecture of the app app and summarize the results of experiments conducted under various conditions, including onboard commercial aircraft, near radioactive sources, and across different geographic regions. Finally, we discuss straightforward use cases in educational settings and explore the broader potential of smartphone-based observation tools to bridge science, education, and public engagement.
Takano et al. (Tue,) studied this question.