A form to enter user information (name, age, sex, height, weight, corpulence) to optimize the calculation of the alcohol absorption curve. Several profiles can be created. - A step-by-step guideline on how to measure your blood alcohol concentration by exhaling into the breathalyzer: 1. Connect the smartphone to the device via Bluetooth®, 2. Initialization and preheating of the breathalyzer, 3. Measurement of the driver’s BAC, 4. Calculation and transmission of the result to the mobile terminal via Bluetooth®, 5. Display of the driver’s BAC result on the mobile terminal accordingly to the legal alcohol limits of the county they are currently in, 6. Alcohol elimination curve evolution follow-up, 7. If the driver’s blood alcohol level exceeds the legal limit, the application offers a 24/7 drive-you-home service to pick the driver up at the very location from which the request was issued.