Best Rental Property Expense Apps for Tracking/Taxes

Just closed on first house! For the first one, tracking expenses won't be too difficult, but I'm looking to setup processes in place to automate and streamline it to scale. 

With that in mind, what mobile apps (prefer all to do from my phone as it's always accessible) are the best at tracking miles, receipts, anything else that can be depreciated or deducted from my taxes, and easiest to use (my Dad is wanting this as well so user friendly huge plus). 

Thanks!