IPhone 4 has all the features of the iPhone, only major changes to the iPhone 3G are listed below. The most obvious difference is a new industrial design. The primary structure is a stainless steel frame that doubles as an antenna. Inside the device between the two panes of glass chemically strengthen the aluminosilicate. Other changes include Apple A4 processor, high-resolution displays, marketed as "Retinal Display" and "embedded video conferencing application for face time.