On October 4, 2011, Apple discontinued the original iPhone 4 (GSM) with 16 GB or 32 GB of storage, and introduced this lower-end model with 8 GB of storage. Although it is similar to its predecessor, this model sometimes referred to as "Revision A" has a variety of different identifiers (most notably the unique iPhone3,2 Model ID), and EveryiPhone.com has documented it as its own model accordingly.

Like its larger capacity predecessor, this 8 GB iPhone 4 uses an all stainless steel body design with an ultra high-density 3.5-inch, IPS, LED-backlit 960x640 326 ppi multi-touch "retina" display, mobile and data antennas integrated in the "metal band" that wraps around the sides of the phone, and a chemically hardened "aluminosilcate" glass front over both the display and a black or white glass frame and a chemically hardened black or white glass back, as well. Regardless of color, both the front and back have an "oleophobic" oil repellent coating.

Also like its larger capcity predecessor, this 8 GB iPhone 4 has dual cameras -- a 5 megapixel HD video/still camera (720p at 30 FPS) with a "backside illuminated sensor," a 5X digital zoom, and an LED flash on the rear and a VGA quality video/still camera on the front designed for video conferencing over a Wi-Fi network with Apple's included "FaceTime" application. It has dual noise-cancelling microphones also.

This iPhone 4 (GSM, Revision A) is powered by an "Apple A4" processor of unspecified speed, has 512 MB of RAM, and has 8 GB of internal storage. Network support includes UMTS/HSDPA/HSUPA (850, 900, 1900, 2100 MHz) and GSM/EDGE (850, 900, 1800, 1900 MHz). 802.11g/n and Bluetooth 2.1+EDR are supported as well. It has a digital compass, A-GPS, an accelerometer, and a 3-axis gyroscope, too.

Apple reports that all iPhone 4 models provide "up to" 40 hours of audio playback, 14 hours of talk time on 2G, 7 hours of talk time on 3G, 6 hours of Internet use on 3G, 10 hours of Internet use on Wi-Fi, 10 hours of video playback and 300 hours of standby time.

This lower-end 8 GB "Revision A" iPhone 4 (GSM), introduced October 4, 2011, was sold for US$99 subsidized by a two-year AT&T contract and available unlocked in the US for US$549.

On September 12, 2012, Apple dropped the price of this 8 GB iPhone 4 (GSM, Rev. A) model to US$0 with a two-year contract or US$450 unlocked and contract-free. It was discontinued on September 10, 2013, with the exception of mainland China, where it remained available for RMB 2,588 until September 9, 2014.

https://everymac.com/systems/apple/iphone/specs/apple-iphone-4-rev-a-specs.html