Not only lets you track fuel efficiency and auto costs, but you can also schedule and track your future maintenance, like oil changes, tire rotations, etc. MyAuto will warn you when your next maintenance is due.

Other Features:
-Price includes all features, comparable to other 'pro' versions.
-Generates service schedule out to the next 50,000 miles.
-Track multiple vehicles.
-Trial mode is full featured, but allows 1 vehicle and 10 fuel receipts.
-Track costs by the categories that you specify.
-Use camera to keep warranty and maintenance receipts.
-All entries are fully editable from history.
-Backup and restore data to either SkyDrive or Dropbox.
-Add your vehicle's photo.
-Import fuel receipts.
-Create Wide Live Tiles by vehicle and function.
-Easy entry of fuel and maintenance costs.
-Enter multiple services on one maint receipt.
-Export to Excel.
-Calculate planned trip fuel costs using historical fuel rates.
-Uses GPS to fill fuel stop location names on subsequent visits.
-Context sensitive help.
-Fuel graphs:
-Customizable timeframe
-User defined moving average
-MPG US, MPG Imp, L/100km, Km/L
-Total cost
-Price
-Miles (kilometers) per day
-US Gallons / Imperial Gallons / Liters
-Cost charts (bar & pie):
-Fuel costs
-Maintenance costs by service by year
-Drill down to more detail by touching bar or pie slice
-Summary statistics:
-MPG, best, and worst
-Fuel cost
-Maintenance cost
-Other cost
-Cost/Fillup
-Miles(km)/$
-Cost/Mile(km)
-Cost/Day
-Miles(km)/Fillup
-Summary statistics time periods:
-Year-To-Date
-Prior Year-To-Date
-12 Months
-Prior 12 Months
-Lifetime