DroidBot is an Android application exerciser like Monkey. It is better than Monkey in malware detection because it is aware of the static information and dynamic information of the target apps. Currently the main limitations of DroidBot are about coverage: 1. How to measure the test coverage? Currently DroidBot use the amount of DroidBox log as a metric, which is not a standard metric; 2. How to improve DroidBot’s test coverage? Currently DroidBot cannot reach some states of app due to various of reasons. I would like to address these issues in this summer.