As of May 2010, Olaf Greck has taken over the development and support of Fuel Log. Mr. Greck has agreed to keep Fuel Log free, and open source the project.
http://itunes.apple.com/us/app/fuel-log-3/id371496366?mt=8
This version will be removed from the App Store in the near future.
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April Fools special: Fuel Log is now free forever!
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Works with iPod Touch, iPhone, iPhone 3G and iPhone 3G S running iPhone OS 2.1 and up.
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Graphically track fuel efficiency for all your cars. Synchronize your data with Google Spreadsheets. Over 3000 copies downloaded in October 2008.
Read our general FAQ at
http://puremass.com/mobile/fuellog.html
Read our data import and export FAQ at
http://puremass.com/mobile/fuellog-sync.html
Decreasing fuel efficiency could mean low tire pressure, aggressive driving or stop-and-go traffic. However sometimes it could indicate serious car trouble.
Fuel efficiency is also known as fuel economy and is measured in miles per gallon (mpg), kilometers per litre (km/l) or litres per 100 kilometers (l/100km).
Please note that the mpg number is not always equal to total distance divided by total gallons. For example, if, with a full tank, you drive 200 miles and choose to buy only 1 gallon of gas, the mpg is not 200 miles divided by 1 gallon. It is 200 miles divided by the number of gallons needed to fill up the tank again. So the miles-per-gallon and cost-per-mile numbers are computed from full tanks between the dates you choose. The entries before the first full tank and after the last full tank are ignored when computing and plotting these numbers.