MPG Calculator allows you to calculate your fuel economy and keep a history of your MPG figures. You can also generate a graph over a customisable timeframe to see if you are being more or less economical.

Every time you fill up you can enter your odometer/milometer reading to automatically calculate the number of miles you have travelled, meaning all you have to enter is the price of fuel and total spend.

The app also allows you to save the graph to your Pictures folder, making it even easier to compare your MPG with your friends.