In Theory: Yes, ask any Apple Store personnel they will tell you so. In Practice: Not everywhere, Not all the time, Not as fast as locally sold iPhones. Warranty issues depends on iPhone models, regulations of the countries and Apple’s policy. Although they all look the same, Apple usually sells 3 different models for every generation of iPhone. One model for Japan market. One model has more CDMA capable modem, however it supports GSM bands. One model has less CDMA capable modem for GSM based markets. In United States, Apple sell both CDMA and GSM models. In Europe, they sell GSM models. For other details about your iPhone model you could visit this web page Identify your iPhone model Although you can easily use your new iPhone almost everywhere, you will not get at least 1 year international warranty everywhere equally. Regulations are differ from country to country. If you bought an iPhone from US, you could get it repaired in Europe, but not in Turkey. Apple Turkey do not give any service to the US CDMA based iPhone, however they give service to European GSM iPhone. Apple Policy changes for some circumstances. Hong Kong doesn’t offer any service for the latest iPhone from time to time, if you bought it from US. Usually when new iPhone came out. Most Apple Stores in Europe don’t stock CDMA Models or their parts. Let's say your CDMA iPhone had a big issue about hardware, it is very likely you have to wait longer in Europe to get it repaired. Even if they need to change the iPhone completely, Apple policy dictates them to change it with the same exact model.