IPhone 4 is the successor to the iPhone 3GS. It is particularly marketed for video calling, and easy usage of media such as books and periodicals, movies, music, and games. It was first released on June 24, 2010 in the United States, the United Kingdom, France, Germany and Japan at the same time.
The iPhone 4 runs Apple's iOS operating system, as the previous iPhones, the iPad, and the iPod Touch. The iPhone restricts users from running any software that is not explicitly approved by Apple and distributed via its App Store.
The most noticeable difference between the iPhone 4 and its predecessors is its new design, which incorporates a stainless steel frame that acts as the device's antenna.
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