Work trips can be exhausting and full of small expenses that quickly add up. Between the Ubers to and from the airport, the snacks to keep up the energy, and the long dinners with clients, spending can quickly sprawl out of control. The last thing you want upon returning is to search through a voluminous pile of crumpled receipts only to find they’re not all there.

WIRED and Condé Nast Traveler are here to help. Bringing together our expertise on software and travel, we picked a few of our favorite apps for tracking expenses on work trips. These could be worth trying out during your next big conference or even adopting as a wider organization. Do you have a reliable option that you trust and it’s not included on this list? Make your voice heard in the comments.

Expensify

Expensify is probably the best app for the widest number of people, from freelancers to bigger staffs. It includes all of the must-haves like receipt scanning, distance tracking, and easy categorization as well as a way to manage how you submit the reports and who is involved with the approval process. It’s not too flashy overall, but integrations with other apps commonly used on work trips, like Uber, Delta, and Workday, are nice to have.

Expensify for iOS, Android, and macOS

SAP Concur

Concur is popular with larger enterprises for handling travel; we’ve used it a few times for work trips ourselves. While the SAP Concur app has some rough edges, it’s worth having on your smartphone if that’s the expense protocol used where you work. Like all of these picks, you can take photos of your receipts in the app to streamline the process. Are you driving? Automatic distance capture can help you file those mileage reports as well.

SAP Concur for iOS and Android

This story is part of The New Era of Work Travel, a collaboration between the editors of Condé Nast Traveler and WIRED to help you navigate the perks and pitfalls of the modern business trip.

Zoho Expense

Like many other expense apps, Zoho Expense lets you save your corporate credit card on the platform and scan receipts as you go. The app then helps you categorize and itemize expenses and extract important details. Hitting the road? No need for guesswork; you can track car mileage with the click of a button to get accurate reimbursements for driving time. You can also calculate your petty cash spend, and businesses can regulate employees’ daily allowances with customizable rules made just for them. It’s also one of the most budget-friendly expense apps, with free plans available for small businesses (three users or fewer) and a premium plan available at just $7 per month.

Another time, I was looking for flights within French Polynesia for my honeymoon. I knew that domestic flights were running around $330 round-trip, but Travelocity priced it instead at $33 due to a currency conversion issue. It’s just a matter of paying attention, looking at the fine print, and meeting other people and sharing opportunities with them.

Is that how the blog started—a passion for sharing the fine print?

When I lived in Washington, DC, in 2002, a bunch of people I knew were starting political blogs, but I didn’t feel like I had something unique to say that nobody was saying in that space. I thought, what is it that people ask me about? So I just started writing up travel tips. One weekend in May I set up a free account at Blogspot.com and started writing for, you know, 30 people reading it, and then 500, and then 1,000. Last month, June, blog traffic dipped a bit to 5.5 million visitors, but in March it was up to 7.5 million.

All right then, let’s talk numbers. Every point system feels a little different than the last. It’s hard to know what, say, 100,000 miles is really worth when it comes to any given loyalty program. What’s your method?

So, I have a close idea of the value of each currency. I value a Marriott point at 65 basis points, for example, and a Hilton point at around 40 or 45, which is about where I value an IHG point, whereas I value a Hyatt point at 1.4 cents, which is around what I’m valuing an American and a United mile at. I’m valuing a Delta mile at about a penny, a Virgin mile at about nine-tenths of a cent.

Using those metrics as a rule of thumb, how do you make the most of your miles?

You want to think about the value of miles as a private currency. There’s no central bank, and it’s going to be subject to a given price level. The simplest model for this is the same sort of analysis you would do with inflation for a government-issued currency. Take the simple monetarist formula, MV equals PQ. The amount of money in the economy times velocity, or the speed at which it’s spent, is going to be equivalent to the amount of Q, quantity, the amount of goods in the economy, and P, the price level, right?

Yes, right. I knew that.

Price is affected by the quantity of seats on planes. Airlines have gotten quite good at what they call capacity discipline and not flying flights that aren’t selling. They’re printing a lot more miles than are being redeemed in a given year, and there are a lot more ways to earn the miles.

How can a newbie get started?

Don’t leave miles on the table. Sign up for programs. Track your points. I use AwardWallet, but keep track of your accounts however you want to do it. Grab your account number when you’re buying something online and go through a shopping portal. Maximize it by comparing portals, whether it’s something like Savewise or Cashback Monitor.

You sound like someone who, like any good points hacker, knows their way around Microsoft Excel.

I don’t really use spreadsheets. I have a really good memory, and I’ve been paying attention to this stuff for almost 30 years.

A version of this story originally appeared on WIRED.