Place your smartphone in a vehicle, calibrate the sensors by clicking on a button and select the range for the visualization (depending on the power of the vehicle). Now you are ready to visualize the GForce while driving like in a racing car! Please take care when using this app and don´t keep yor eyes out of the road for a long time, safety first! And of course, respect also the rules. If you have some suggestion. miss some feature or find some problem do not hesitate on contact the develop