The autonomous flight system can easily track and monitor the target in the scene where the UAV needs to fly accurately and monitor the target in real time.When people obtain the target location information as the specific longitude and latitude coordinates,the manually operated aircraft cannot fly to the location accurately,which creates great difficulties for the use of UAVs to take fixed point flight photos.To solve this problem,this paper develops a UAV autonomous flight mobile phone application based on Android studio as the development platform,using the DJIMobile SDK and DJI UX SDK development components.The application mainly consists of five program modules,which can realize precise longitude and latitude flight,interest point circling,one button takeoff,automatic return,image and video upload and download,and real-time UAV screen broadcast,and can set flight altitude a series of parameters such as flight speed,flight path mode,PTZ orientation,and dwell time at the waypoint.The results of many field tests show that the UAV can fly to the target point independently according to longitude and latitude,and finally hover over the target with an error of less than 10 meters,greatly improving the UAV's ability to fly accurately and track and monitor.