I’ve been using the app “Car Minder Plus” for the past year and a half to document my gas mileage and repairs. It allows me to enter a garage of different cars and keep track of maintenance and service. Since I don’t have a fuel gauge it helps me keep track of how many miles I’ve gone since the last fill up, then shows my overall fuel mileage over 3 months, one year and lifetime.
This charts MPG over the course of 18 months. Note the dip after AMM broke.
Whenever I have a problem with the car I document it in the app so I have dates and mileage of when the problem occurred. I can also enter the expected time and mileage between services so they will come to my attention later and show me how dreadfully behind I am on my maintenance schedule.
My mileage is low enough that it's the date intervals that trigger the red light, not always mileage. Each of these items and their intervals can be set by the user.
These screen shots document the problem I had with my air mass meter. In the first you can see my mileage dive from over 20 mpg to below 15 mpg after I stalled in flood waters last August. I was pumping out unburned fuel for months before the problem was diagnosed and fixed. I was sure to document it all for future reference.
The "Repairs" area allows you to document anything and everything that happens to your ride.
Each repair item records date, mileage and your notes.
A bonus for “Car Minder Plus” is that you can email all your records from you iPod or iPhone. They come in a PDF file that you can print and hand to a mechanic if need be. Overall a useful app, I just have to be careful not to get my iPod Touch covered in motor oil and PB Blaster.