You get 54 cents for every mile you drive work -- provided you remember to track it. Mileage is money. That's the truth for the self-employed, the small-business owner and just about anyone who drives for work. For every mile you log, you get to deduct 54 cents from your taxes. OK, but how do you log those miles? In the old days, you jotted odometer readings into a notebook, then spent a lot of time with a calculator come tax-time. Then you had to transcribe all that data into a form or spreadsheet or whatever. Yuck. Thanks to modern phones and apps, however, you don't have to mess with any of that anymore. Hurdlr will automatically record your trips, then generate a report you can use for reimbursement or tax filing. Amazingly, it's free. My first drive, auto-tracked by Hurdlr. I just earned a $2.83 tax deduction! There are lots of other apps -- most notably Everlance and MileIQ -- that can track your drives, but nearly all of them cost money, either up front or on a subscription basis. The cheaper ones tend to have clunky interfaces, or at least require more manual input regarding each trip. Hurdlr lets you manually enter drives, but it can also work automated GPS magic behind the scenes, detecting the start and end of each trip. Needless to say, there's a battery consideration here: This automated tracking requires full-time GPS access, so using Hurdlr will definitely affect battery life. But that's true of any tracker. My advice: Try the app for a week or two and see just how big that impact is. It might be worth the hassle of recharging a little more often in exchange for a complete, IRS-friendly mileage report that's generated (in PDF or Excel format) with just a few tap. Hurdlr also manages finances; you can link bank accounts as well as services like FreshBooks and Uber, then assign income and expenses alike to their relevant categories. If you manually add an expense, you can use the app to snap a photo of a receipt, then sync that receipt to a cloud account like Dropbox or Google Drive. In short, it's a very comprehensive app, one with a pretty interface and straightforward layout. And for now it's totally free, as it has been for over two years.