Fuel Mileage Wizard

Preparation
To be done the first time, prior to begining the process of measuring your fuel economy.
A - Fill your fuel tank to full.
B - Reset your trip odometer.
Instructions
1 - Drive your vehicle as normal. When your tank is down to 1/4 or less, proceed to next step.
2 - Fill your tank to full.
3 - Enter the fuel amount you just purchased and the trip odometer reading into the app. Optionally type in a vehicle number or name. Be sure to select the correct units and press calculate. Note your fuel economy figures, and optionally press save*. Reset your trip odometer for next time. Repeat process starting at step 1.
*If you press save, the output figures are saved to a file called FuelMileage.txt in your download folder. This file will contain 1 line for each time you pressed save. Over time you can tell if your mileage is better, worse or generally the same. If you open this file using a spreadsheet app, you can add your own custom calculations to the data, and save it in a different file that meets your own personal needs.