This is the first in series of posts that will describe my experiences using an iPhone while traveling around the world. This post is just general tips. The follow on posts will describe our experiences in the countries I have traveled.
We typically get a "local SIM" at the airport upon arrival. This is also called a "pre-paid SIM". This will save you a lot of money because by paying up front (hence pre-paid), you know you will not come home to a huge phone bill. You'll typically need to spend between $20 to $30 (USD) to get a SIM and phone plan. This beats even the cheapest international plans from US phone companies.
You will need to decide if you want data (Internet), voice, or both. I always opt for both, if possible, as having voice will give you a local phone number.
Having a local phone number comes in very handy. You can call hotels or restaurants to get directions easily. Also, in Paris, we found it was not possible to call and order a taxi without having a local phone number.
Having data (or Internet access) is great while traveling. The big thing is using Google Maps to find your way around. This can be invaluable and can save a lot of time. It also allows you to keep up with all your social media (Facebook, etc), email, or anything else you'd do online with your phone in your home country. You can also use various apps to call home for free or very cheaply. Our current favorite is Magic Jack.
To use your phone with a lcoal SIM, you need an "unlocked" phone. Most mobile phones in the United States are locked to a carrier like AT&T or Verizon. Check with your carrier before leaving for your trip to avoid disappointment during your travels. Locked phones will not work with another phone company.
For the best experience, research mobile phone companies in the countries in which you will be traveling. Some carriers work better in some parts of a country, but not all. Some carriers work well in cities and will not have good coverage in more rural areas. Again, check in advance by doing a few Google searches before you leave.