I've spent 6 months traveling the world on business, and I've found the perfect phone hack to save time, money, and aggravation

• Business travel means traveling to foreign countries that work far different from the US. Having cheap internet access can make a lot of things, from navigating a new city to sending emails, a lot less stressful.
• Using foreign SIM cards is the cheapest and most hassle-free solution.
• In order to use a foreign SIM card in your phone, you'll need to get your phone "unlocked" by your mobile carrier. Make sure to call ahead as sometimes it can take a few weeks for the request to go through.

In the last six months, I've traveled through Hong Kong, China, Singapore, Indonesia, Korea, Russia, Israel, Jordan, Cyprus, and, finally, Greece for business.

I don't have time before I land in a country to figure out the myriad systems that make a country unique. Like most modern people, I've become accustomed to using internet to figure things out: everything from how much a taxi should cost to whether I can drink the water.

While the situation has improved since years past when I would pay AT&T $60 for a meager few hundred megabytes of data, paying for an international plan is still costly and inefficient.

AT&T's plan now is $10 a day for an international day pass, which gives you your regular data plan plus unlimited talk and text. Verizon's plan is more or less the same. If you're traveling for an extended period, that comes out to $300 a month on top of your regular phone bill.

Yikes.

With a little planning and forethought, you can use your smartphone abroad without worrying about eye-gouging roaming fees or racking up international "day passes." All you have to do is buy temporary SIM cards in whatever country you are visiting and you'll be enjoying cheap pay-as-you-go internet.

In order to use temporary SIM cards abroad, you'll need to "unlock" your phone first.

Most smartphones are "locked" to your carrier, like AT&T or Verizon. Companies do this to keep you in their network, but thanks to a law passed in 2015, carriers can no longer deny a request to unlock a phone.

While you can buy phones that are already "unlocked" - Insider Picks has a nice list here - you should be able to get your regular phone unlocked. Just make sure you start the process a few weeks before leaving as many companies will make you jump through a few hoops.

For a more comprehensive how-to, Digital Trends has a great article with all the ins and outs for every major US carrier.

Once a phone is "unlocked," it no longer needs to be used with a specific carrier. That means when you travel abroad, you can buy a SIM card from any company, pop it in, and your phone will work.

Most countries that I've visited make this process super-easy. In just about every airport, in the arrivals area, there will be a kiosk from a local telecom provider that sells temporary SIM cards. These SIM cards are valid for a predetermined period of time (often 1-3 months) and come preloaded with a certain amount of talk, text, and data. In addition, if you use up any of the above, they are easy enough to reload either online or at a local convenience store for a few bucks.

In general, I've never paid more for than $20-40 for a SIM card with data in a foreign country and I use data relentlessly. The most expensive country thus far was Korea, where I paid $60, but that was for unlimited data.

I use my SIM card to tether to my laptop so I can get work done when the hotel Wi-Fi is crappy; I post to Instagram 5-10 times a day; I navigate everywhere with Google Maps; and I use WhatsApp and Skype to make tons of business calls every day. I run through 2-4 GB or more a week.

But still, GBs of data are often so cheap in foreign countries that it hardly matters. Even $60 a month is a fraction of what I'd be spending on international day passes or roaming charges.

The one major annoyance to using foreign SIM cards is that (a) you'll have a new phone number that you need to remember and (b) if you use iMessage, it will act wonky unless you link your account to your email address beforehand.

But those are small prices to pay for a cheap fountain of internet abroad.