Mobile phones have come a long way since their introduction over 30 years ago. Phones are smaller, weigh less, and do more, carrying data as well as voice. Phones not only make telephone calls, they send e-mail and text messages, take and send photographs, play games, and access and browse the Internet. And mobile phones are everywhere. By the end of 2009, mobile cellular subscriptions worldwide numbered approximately 4.6 billion.1 Neither age, nationality, nor economic status represents a barrier to owning and using a mobile phone. The first phones may have been novelties, but mobile phones now are a necessity, especially for the under-35 demographic.