From TARDIS Index File, the free Doctor Who reference.

Mobile phones were handheld mobile communication devices originating on the planet Earth, they became prominent amongst much of the population in the early 21st century.

Rose Tyler, Martha Jones and Donna Noble had their mobiles adjusted by the Doctor (Ninth and Tenth Doctors respectively) to have 'Universal Roaming'. These became known as Superphones as they were able to call anywhere in time and space and could apparently work in areas of no service such as the Cabinet Room. The Doctor also modified Barcly's phone in this manner, but he did it so he could communicate with UNIT. It is unknown what he did with this phone afterwards, if he undid the Universal Roming and gave it back, just gave it back as is, or kept it. (DW: The End of the World, 42,The Doctor's Daughter)

Anji Kapoor carried her mobile with her when she began travelling with the Doctor, and was even able to use it when she travelled into her future. (EDA: Escape Velocity, Trading Futures)

The Eighth Doctor also set up mobile phone-like devices for Ani and Fitz Kreiner when they spent a selective amount of time on certain planets. (EDA: The Book of the Still)

The Ninth Doctor was shown to have his own cellphone in (DW: Boom Town), but it was never seen again. The Tenth Doctor would later keep another phone given to him by Martha Jones.

Sarah Jane Smith, Josh Townsend and Natalie and their respective friends frequently used mobile phones to keep in regular contact with one another. (BFA: Sarah Jane Smith (audio series))

See also

• Telephone
• Superphone

From Grand Theft Wiki

Badger phone in GTA IV, without Badger logo.

The phone is a portable communication device that has been carried by the protagonists of all the Grand Theft Auto games since Grand Theft Auto: Vice City, with the exception of Grand Theft Auto: Vice City Stories. In the GTA III era, the phone was essentially cosmetic, and could not be used by the player to make calls at will, but its use has been expanded in Grand Theft Auto IV.

Grand Theft Auto: Vice City

In Grand Theft Auto: Vice City, Tommy Vercetti retrieves a phone from Leo Teal during "Back Alley Brawl", allowing him to receive calls from in-game characters about missions or other topics. The phone's design is based on early commercial mobile phones from the 1980s.

Grand Theft Auto: San Andreas

In Grand Theft Auto: San Andreas, Carl Johnson has a phone which he uses to make and receive calls. Again, these may be about missions, they may relate to the general story, they may be tips from other characters, or they may serve no particular purpose — for example, the prank calls CJ receives from Catalina. The phone's design is that of an early flip-phone, with a small display for numbers.

Grand Theft Auto: Liberty City Stories

In Grand Theft Auto: Liberty City Stories, Toni Cipriani retrieves a phone from a deceased Sindacco member in "Snuff". This phone is presumably the phone he uses from then on, as Toni originally called using a pay phone in "Home Sweet Home". The phone's function is similar to those in GTA Vice City and GTA San Andreas.

Grand Theft Auto IV

The use of the phone is greatly expanded in Grand Theft Auto IV and its episodes. The player can use the phone (given to Niko Bellic by his cousin Roman during the second mission), and a camera phone from Playboy X, during the mission Photo Shoot to make calls, a new feature to the series

Niko can now call his friends and girlfriends to hang out or go on dates respectively, and can now receive text and picture messages from people. Niko can also use his phone to access cheats, go to multiplayer, and call emergency vehicles (like Police Cars, Ambulances, and Fire Trucks) for assistance. The second model of phone is equipped with a camera, available for use anytime, and used in certain missions. Use of the phone can also trigger some missions, like the The Holland Play, and pre-emptively calling some characters may trigger story-related dialogue more quickly.

The theme and ringtone of the phone can be changed via a website on the in-game internet after the second model of the phone is acquired. The two phones used by Niko during the game are Badger and Whiz brand phones.

Exclusive features

In the PS3 version, an additional option is available in the phone. It is a SIXAXIS tutorial that teaches the player on how to use the SIXAXIS controller in the game. In the PC version, the Video Editor is an option in the phone. In both versions, the game will exit out of gameplay and all unsaved progress will be lost.

Phone exploits in Grand Theft Auto IV

If the player has damaged a vehicle to the point where the engine won't start, the phone can be used to 'jumpstart' it by calling any number or contact — the engine will spontaneously function again, although no damage will be repaired. For convenience's sake, one can cancel the phone call as soon as "Calling..." is seen on the phone's display — the engine comes back to life as soon as the call is initiated.

In the console versions of the game, the phone can also be used as a kind of 'super handbrake', to instantly stop any vehicle, no matter the speed. Initiating the camera while driving will instantly stop the car — the player can leave the phone open to the 'Camera' menu option, and then press X (on PS3) or A (on Xbox 360) when they want to stop. This is presumably a bug, and was fixed in the PC version — activating the phone camera while driving on PC will merely change the game camera to the 'hood cam' perspective, and activate the phone camera as normal. As this exploit requires a camera function, it can only be performed once the player has acquired the second model of phone.

Trivia

• In GTA IV the second model of the phone can be customized with themes and ringtones from websites. On the streets of the Liberty City random pedestrians will sometimes take out their phones to receive a call. If you look closely at the civilians phone, you will notice that the theme on their phone's screen will be the same as your current phone theme.
• In The Lost and Damned and The Ballad of Gay Tony, the protagonists of each (Johnny Klebitz and Luis Fernando Lopez) also have phones the player can use in the same way Niko's is used. Each character has a different type of phone than the others, and Johnny and Luis each have a unique theme for their phones. Johnny Klebitz's phone is more rounded than Niko Bellic's rectangular phone and the numbers on the keypad are more separated due to each number  being on a separate button, whereas the numbers on Niko's phone use a "key strip" layout used on phones like the Motorola Razor. Johnny's phone has a unique "Lost MC" theme featuring The Lost Motorcycle Club's patch. Luis Fernando Lopez's phone appears to be more high-end than Niko and Johnny's phones and is round, similar to Johnny's, and has a glowing blue keypad and a unique "Club" theme. Luis' phone resembles a LG KE850 Prada.

Gallery

The mobile phone in GTA 1. Spoken text is displayed to the right of its image.	The mobile phone in GTA Vice City.	The mobile phone in GTA San Andreas.	Carl with his mobile phone in GTA San Andreas.
The mobile phone as a pickup in GTA Liberty City Stories.	The mobile phone in GTA IV renders its screen and keypad into a display on the lower right of the screen; this is replicated on the 'actual' phone Niko holds, as seen here.