Whenever you're traveling to another country, it's essential to plan for how you will stay connected. Simply using your phone overseas will result in a bill that could reach into the thousands of dollars. Here's a breakdown of the options you have:
Use Wi-Fi Only
The most cost effective solution overseas is to not use data at all on your smartphone, and instead rely on Wi-Fi. Your hotel will likely include internet, and most coffee shops should have a hotspot to connect to as well. Then if you need to make a phone call, you can use a service like Skype or Tango. Skype Out lets you call regular phones, and it costs just $2.99 a month. If you'd like to have a Skype number to receive regular calls on, it costs $5 a month.
Buy a Local SIM From a Local Provider
If you tell your wireless provider you'll be traveling overseas, they will likely unlock your phone so you can buy a local SIM when you get to your destination. You won't be able to use your current phone number, but you will be able to get more affordable data. For more information on the best networks and plans in other countries, check out the PrePaidwithData Wiki. This 3G mobile hotspot from Huawei is a good option that will work with multiple carriers overseas as well.
International Roaming Plans
Adding an international roaming plan from your wireless provider may be the most convenient way to get data overseas, but it is also the most expensive. And, if you're a Verizon or Sprint customer, you'll have to make sure your phone is a world phone. Verizon and Sprint both use CDMA technology, while the rest of the world uses GSM, so your phone will need to support both. The iPhone 5 and 5s are world phones.
Depending on where you go in the world, costs could be as much as $30 for just 15 minutes of talk time. Text messages can run $10 for 50 messages, and data can cost $30 for only 120 MB. This would require you to keep data turned off until you absolutely need it. Otherwise, your phone will use up all of your allotted data just by checking email and refreshing app data. (Prices based on AT&T's international plans).
If you're a T-Mobile subscriber, T-Mobile offers unlimited data in most countries over their slower EDGE network at no extra cost. Find out more about T-Mobile's international data plans here.