 applications that give parents the ability to track their children's locations and to find friends who are in the area. 4G networks also have GPS capabilities. The Driving Force of Smartphones A smartphone is a handheld mobile device that can be used for voice as well as data applications such as e-mail. It is essentially a mobile handheld computer capable of being used for voice calls. The first widely used smartphone was RIM's BlackBerry. In 1999, the BlackBerry was the only smartphone used by business people. The Black- Berry appeals to businesses because of the BlackBerry server's security features, including its capability to strongly encrypt transmissions. In 2007, Apple introduced the iPhone. It was the first smartphone that was adopted by both consumers and business people alike. It created a seismic shift in handset designs, and fueled the demand for touchscreens and sleek, easy-to-use user inter- faces. The icon-driven main screen made using the phone highly intuitive. The iPhone, which was initially available exclusively from AT&T Mobility, created a sensation and the device became a status symbol. It also created enormous traffic jams on AT&T's network as people used their iPhones for e-mail and functions such as the continuous updates of stock market ticker tape. AT&T Mobility stated that traffic on its network increased 5,000 percent in the first three years that the iPhone was available. Handheld Devices and Tablet Computers Following the success of the BlackBerry and iPhone, other manufacturers have introduced their own smartphones. Some of these new devices use Google's Android operating system. Unlike the iPhone, which is manufactured under the strict direc- tion of Apple, Android-based phones are made by a variety of manufacturers such as Samsung and Motorola Mobility. Some are positioned for consumers who want a less costly handset than the iPhone; others are targeted at consumers who want higher-end handsets. In addition, they are not sold under exclusive contracts to a limited number of car