I noticed the avg fuel economy was showing differently between the app and my account on the Fuelly site. After some time, I realize that the app only has records from the last 14 months (it goes back to Nov 25, 2013). The web site shows the (correct) records all the way back to 2010. I tried exporting all the data, creating a new car in my account, and importing the date to that car. I get the same results.
Has there been any update for this? I am new to fuelly and I am noticing a similar problem. I transferred all of my data from GasCubby Free for my current car. The website shows 133 fuelups that date back to May 2013, but the iphone app only shows 100 fuelups dating back to November 2013.
This also makes the MPG show a different figure between the phone app and the website.