This app feature is to be a stopwatch for two drivers at the same time. Also, you can select a number of sectors you want to divide the track. With the same button, you start timing you will end the last lap and once the session ended you can stop timing with the "End session" button. After you end your first session the "View results" button will be enabled and the color will change to green. Keep in mind that when you start timing again the previous session will be deleted.