I'm a freelance software consultant working remotely and there isn't much I can expense as far as I know (working from home costs, hardware, software, insurance, accountancy fees, mobile bill).
You're only supposed to expense the items which were actually for business purposes, and no app can figure that out for you if your record-keeping throughout the year was sloppy. I don't think it will fly when you're sitting down uncomfortably with an IRS auditor if your defense is that some app told you to do it.
I live in NL and (I checked with my accountant), I can deduct the cost of coffee I get at the cafe where I work, provided that I drink it while working.
Without travel expenses, purchasing lots of hardware or online service costs for running a project, I'd be interested in what people are expensing if their expenses are above say £5K a year.
However in case you get audited, make sure you keep reciepts (not just record of payment) and can justify it as being a food-while-working or bizdev expense.