According to Tianyancha's intellectual property information, on March 8th, Apple's patent for "collision detection on mobile devices" was announced. The present invention patent discloses an implementation scheme for collision detection on mobile devices (such as smartwatches and smartphones). In some schemes, a method includes detecting collision events on collision devices through at least one processor, extracting multimodal features from sensor data generated by multiple sensing modalities of the collision device through at least one processor, and calculating multiple collision decisions based on multiple machine learning models applied to multimodal features through at least one processor, And determine through at least one processor based on multiple collision decisions and severity models that a serious vehicle collision involving collision devices has occurred.