Apple iPhone 4S uses a wireless chipset from Qualcomm as well as an Apple A5 chip with 1 GHz dual-core processor with 512 MB of DDR2 RAM, according to iFixit, known in the technology industry for stripping down and revealing the innards of Apple devices.

Compared to the previous iPhone, changes to the radio design include the use of an updated Qualcomm baseband processor, the MDM6610.

In contrast to the iPhone 4 models, the baseband processor is discrete and is no longer integrated with the radio frequency (RF) transceiver. The RF transceiver is the Qualcomm RTR8605, a dual-mode device also met in other handset designs, such as the Hewlett-Packard Veer and HTC Thunderbolt.

Apple also incorporated the Toshiba THGVX1G7D2GLA08 16 GB 24 nm MLC NAND flash memory in the phone, iFixit added.

iPhone 4S also features the same 960 x 640 pixel Retina display that debuted in the iPhone 4 last year.

Some of the other chipmakers identified include Skyworks Solutions (Skyworks 77464-20 Load-Insensitive Power Amplifier module developed for WCDMA applications), TriQuint (TQM9M9030 Multi-Mode Quad-Band Power Amplifier Module and QM66052) and Avago Technologies Inc, which has a power amplifier chip in the phone.

The iPhone 4S will hit store shelves around the globe on Friday.

Compared to Apple's previous model, it comes with a faster processor and a better and more light-sensitive camera.