Diane is going to be traveling to Switzerland and wants to be able to use her phone and tablets locally. Leo says since she uses AT&T's service, she can request that they unlock her phone for the trip so she can buy a local SIM. She's also going to three other countries, and that will cause issues as well.
Brett is going to Paris in a few weeks to make a TV show, and he's concerned about carrying his cellphone. Leo says it's best to get an international data roaming plan. It's not cheap, but it's far cheaper then paying the roaming fees after he gets back. It's also important to have the GPS capability to get himself around.
John wants to know if an unlocked iPhone 5 from Verizon would work when traveling to Europe. Leo says that Verizon is a CDMA carrier, but the iPhone 5 is called a "world phone" because it works with both CDMA and GSM. Verizon set it up so that while CDMA is locked to Verizon, the GSM radio is unlocked for any carrier. One of the chad mods recently went to Japan and it worked great with a prepaid SIM.
Don just got an iPhone from Verizon and doesn't know if he needs the SIM chip. The chatroom says that the SIM chip is for the LTE data plan.
Verizon also sells phones that can be used all over the world and the SIM port is for that purpose.
Leo says that there's a good chance he won't be able to use it all. It's a CDMA phone, and most cell networks overseas use GSM technology. If he upgraded to the iPhone 5, he'd have no problem. The Verizon iPhone 5 comes unlocked and is a world phone, so Eric could buy a local SIM card and use data locally.