Since any app requires that you enter information, why not just have a small notebook that lives in your vehicle. I record mileage on Jan 1. Then let's say I do nothing but personal errands through Jan 3. On Jan 4, when I head out for a shop I enter:
1/1 - 1/3 errands, enter odometer reading. . 1/4 Bank of Ralph, Biloxi. When i return home from Biloxi I enter the odometer reading. That, of course is the reading for the beginning of the next trip. Since I may use the car for only errands for 2-3 days in a row, this method lumps all of those together, since those miles are all "personal use." At the end of the year, I enter the final odometer reading, compute total miles and then add up the few personal miles that I have driven, subtract; result equals business miles for deduction. What's not to like?
Apps are great when they actually simplify stuff. In this case, an app may not do that at all.
Based in MD, near DC
Shopping from the Carolinas to New York
Have video cam; will travel
Poor customer service? Don't get mad; get video.