Mobile Device

A mobile device is a portable, battery-powered appliance with some amount of computing, display and communications capabilities. A wide variety is now available with considerable capabilities.

The most common mobile devices are mobile phones (also called cellular or cell phones, due to their dependence on a network of transmitters located in overlapping "cells" across a region) and handheld computers, of which the best known examples are personal digital assistants (PDAs), the BlackBerry and the iPhone.

A mobile phone has the same basic capability as a land-line telephone but has the advantages of being portable and wireless. It is usually pocket-sized and very convenient to carry.

Evolution of the Mobile Phone, 1992 to 2004. Image source: Wikimedia Commons 

The above image shows the evolution of mobile phones where, over the years, the size has diminished and the functionality has increased. The models from left to right are the NEC Cellstar 500 series, Nokia 2110 series, Nokia 5120, Kyocera 2135, Audiovox CDM8300 and Samsung SCH-A650.

These days mobiles phones come with a variety of features, such as radios, cameras and MP3 players. Even low-end mobile devices allow a user to send out short text messages to another mobile device, known as short message service or SMS. The basic telephone model has been extended to provide functionalities like exchanging picture messages and videos (multimedia messaging service, or MMS), gaming, organizers and even address books. Some of the high-end phones also incorporate Internet connectivity. Another major feature provided by cellular devices is Bluetooth.

Issued in 2007, Apple's iPhone  encompasses a number of features and is regarded as an Internet-enabled multimedia mobile phone. The iPhone's features comprise a camera, an MP3-player, text messaging, and visual voicemail. The iPhone also provides services such as e-mail, web browsing and Wi-Fi connectivity. The iPhone provides users with a variety of functions that users typically enjoy from their desktop computers. When introduced, the iPhone was a unique mobile device in its offering of a flush, multi-touch screen and a minimal hardware interface that featured a virtual keyboard.

Learn about the security of mobile devices from the article Are Mobile Devices Safe.