Need more error checking.
 

Please add error checking when entering miles since last fuel-up. 96,306 miles on one tank of gas is a bit much, as in this example.

Yeah, we have a long way to go in this regard, to make outlier data report errors back to the user so they can see they probably meant to mark off that fill-up as an odometer reading and not miles traveled via tripometer.

Now that we have some data for lots of car makes and models we can probably start to compare fill-ups against the car make/model average and throw up errors for things that are way outside the normal bounds.