The iPhone shares simple mobile phone functions such as calling(newer versions also include a video call ability)and texting,as well as multimedia functions,like file storage and organization,and playing your favorite tunes and videos as well as viewing your favorite photos.
The device also includes Internet and browser-based functions as it allows you to surf the Internet with the help of the implemented Wi-Fi technology.The iPhone can execute a large number of applications (commonly known as Apps).These applications need to be checked and approved by Apple first,in order to work.They can only be obtained by visiting Apple's official online store.Apple has currently registered over 20.000 applications on their webstore from a large number of domains which include gaming,social-networking, GPS systems and maps,and many others.Some familiar names can also be seen,like YouTube or Twitter.
There are currently four models of the iPhone available,the first one being launched in 2007,and the last one in 2010. Although every model brought something new to the table,and improved somehow the device,they all share some characteristics that are iconic for the iPhone, and have resisted through all four upgrades.Such characteristics are the screen size or the button positioning.
The iPhone is known for its lack of physical buttons,as all models have only two physical buttons, except for newer revisions which have side volume keys.One of these physical buttons is the Awake/Sleep button that can be found on top of the device and basically turns the iPhone on or off. It can also work as a mode changer,as it can change the mode to silent if pressed when a call is received.The other physical button is called the Home button and it is called so due to the fact that it closes all apps and redirects you to the home screen.
One must first register the device as a mobile phone in order to be granted access to the multimedia and Internet features as well.This practice is often seen at the subsidized GSM phones,but opposing the GSMs,the iPhone cannot be activated by introducing a code or serial number.However,a man named Jon Lech Johnson discovered a way to bypass this requirement.He unlocked the phone by using some software programs and editing some data in the iTunes binary. He later posted the necessary data on his blog so anyone could unlock their iPhone.
Later on came the iPhone 3G which represented a bigger challenge for hackers as it required an in-store activation.However,this model was also unlocked by registering it from different networks,after shipping the devices over the sea,or at least that is what Apple speculates.The original network on which the iPhones should been registered to is AT&T but only a quarter of the total number of sold iPhones were actually registered to this network.