Mobile phone features

The features of mobile phones are the set of capabilities, services and applications that they offer to their users. Mobile phones are often referred to as feature phones, and offer basic telephony. Handsets with more advanced computing ability through the use of native code try to differentiate their own products by implementing additional functions to make them more attractive to consumers. This has led to great innovation in mobile phone development over the past 20 years.In early stages, every mobile phone company had its own user interface, which can be considered as 'closed' operating system, since there was a minimal configurability. A limited variety of basic applications (usually games, accessories like calculator or conversion tool and so on) was usually included with the phone and those were not available otherwise. Early mobile phones included basic web browser, for reading basic WAP pages. Handhelds (Personal digital assistants like Palm, running Palm OS) were more sophisticated and also included more advanced browser and a touch screen (for use with stylus), but these were not broadly used, comparing to standard phones. Other capabilities like Pulling and Pushing Emails or working with calendar were also made more accessible but it usually required physical (and not wireless) Syncing. BlackBerry 850, an email pager, released January 19, 1999, was the first device to integrate Email.Mobile phones generally obtain power from rechargeable batteries. There are a variety of ways used to charge cell phones, including USB, portable batteries, mains power (using an AC adapter), cigarette lighters (using an adapter), or a dynamo. In 2009, the first wireless charger was released for consumer use. Some manufacturers have been experimenting with alternative power sources, including solar cells.GSM mobile phones require a small microchip called a Subscriber Identity Module or SIM card, to function. The SIM card is approximately the size of a small postage stamp and is usually placed underneath the battery in the rear of the unit. The SIM securely stores the service-subscriber key (IMSI) used to identify a subscriber on mobile telephony devices (such as mobile phones and computers). The SIM card allows users to change phones by simply removing the SIM card from one mobile phone and inserting it into another mobile phone or broadband telephony device.Mobile phones have a display device, some of which are also touch screens. The screen size varies greatly by model and is usually specified either as width and height in pixels or the diagonal measured in inches.Mobile phones have central processing units (CPUs), similar to those in computers, but optimised to operate in low power environments.Other features that may be found on mobile phones include GPS navigation, music (MP3) and video (MP4) playback, RDS radio receiver, built-in projector, vibration and other 'silent' ring options, alarms, memo recording, personal digital assistant functions, ability to watch streaming video, video download, video calling, built-in cameras (1.0+ Mpx) and camcorders (video recording), with autofocus and flash, ringtones, games, PTT, memory card reader (SD), USB (2.0), dual line support, infrared, Bluetooth (2.0) and WiFi connectivity, NFC, instant messaging, Internet e-mail and browsing and serving as a wireless modem.Most mobile phone networks are digital and use the GSM, CDMA or iDEN standard which operate at various radio frequencies. These phones can only be used with a service plan from the same company. For example, a Verizon phone cannot be used with a T-Mobile service, and vica versa.Mobile phones are now heavily used for data communications. such as SMS messages, browsing mobile web sites, and even streaming audio and video files. The main limiting factors are the size of the screen, lack of a keyboard, processing power and connection speed. Most cellphones, which supports data communications, can be used as wireless modems (via cable or bluetooth), to connect computer to internet. Such access method is slow and expensive, but it can be available in very remote areas.As more complex features are added to phones, they become more vulnerable to viruses which exploit weaknesses in these features. Even text messages can be used in attacks by worms and viruses. Advanced phones capable of e-mail can be susceptible to viruses that can multiply by sending messages through a phone's address book. In some phone models, the USSD was exploited for inducing a factory reset, resulting in clearing the data and resetting the user settings.Most current phones also have a built-in digital camera (see camera phone), that can have resolutions as high as 48M pixels. This gives rise to some concern about privacy, in view of possible voyeurism, for example in swimming pools. South Korea has ordered manufacturers to ensure that all new handsets emit a beep whenever a picture is taken.