On a leisure sail boat it's not always easy to know how many fuel do you have on your tank.
Generally you have an engine hour counter and a gauce where you can approximately read how much of your tank is full of fuel.
This application has the purpose to evaluate the liters of fuel you can find in the tank, on the base of engine hours counter.
Pratically the application calculate the liters used during last hours on engine on-time and subract it from the initial tank value.
The application provide several methods of calculating the consumption, according to your engine or to RPM etc.
I suggest you read the help file before using the application