In the app you can log the car business use costs according to the IRS guidelines. It’s worth to read the following guideline to understand the basics for IRS car tax deductions methods.
Log you mileage cost in the “New expense” view, “Standard mileage rate” tab.
Log you mileage cost in the “New expense” view, “Actual car expenses” tab.
Once you put all the expenses, you can use embedded mileage rates (“Settings” view) according to IRS or customized based on you needs.
The summary of the Standard Mileage and Actual Expenses are available in “Main” view in the Tax” tab.: You can easily check which method will bring biggest Tax Deduction.
You can also use detailed view for each method as well as export to CSV (Car expenses full version feature)
If you log all car business use costs and mileage the app will help with estimate of business use percentage.