You must choose circuit and vehicle before starting, then you must press the start button, then the app works automatically. When the app has gps coverage it will start counting the timer, and when you cross the start / finish line, the app will count your laps with their respective lap times. The app will save all the laps and you can close the app or turn off the phone.
The app will automatically uploads the laps to the server if you have internet on the phone, or you can upload it when you connect it to a Wi-Fi.
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