Mazda MPS / Mazdaspeed Fuel Mixer Pro

As for the Lite version, this app allows you to calculate the amount of fuel to be added in tank, based in a selected mix value between petrol and ethanol. Unless the LITE version, this one allows you to save the fuel filled data in cloud, export your fuel logs, select app theme, get warnings to service up your HPFP (High Pressure Fuel Pump) internals (Ethanol slowly damages the internal O-Rings), and more, this app can adjust automatically the selected mix if you don't fill exactly the amounts of fuel commanded by the application, allowing you to fix the gap that you've got while filling up your tank.