Ransomware such as WannaCrypt and Petya have caused significant financial loss and even have endangered human life (e.g., ransomware attack on UK hospitals). Ransomware on desktop has gained much attention from academic and industry. However, we see that the number of ransomware on Android phones remains steady increasing, but gains much less attention. As Android has been the most popular smartphone OS and a substantial number of credentials are kept only in smartphones, the data loss incurs serious inconvenience and loss. Here, we present our deep learning-based ransomware detection system, coloR-inspired convolutional neuRal network-based androiD ransomware Detection (R2D2). R2D2 was originally developed to sweep the malware, but we found it particularly useful in detecting ransomware. A unique feature is its end-to-end training, without human intervention. Such an end-to-end training points out a direction that we no longer need tedious search for roust ransomware features for detection. Most importantly, based on R2D2, we develop techniques to encode ransomware as so-called ransomware image, such that the ransomware from the same family exhibit the same pattern and even non-experts can detect and even determine the ransomware family with their the naked eye.