iPhone 4S

Compared with the iPhone 4, this model replaced the A4 with the dual-core Apple A5 chip and added Siri. The rear camera went from 5 to 8 megapixels and records 1080p video. One model works on both GSM and CDMA networks, with an antenna design that switches between two antennas, and Bluetooth went to 4.0. The glass and stainless steel case looks almost the same as the iPhone 4.

Model number

A1387 or A1431

Model identifier

iPhone4,1

Released

2011

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