The Apple iPhone 4S is available officially on Sprint, AT&T, and Verizon Wireless in the United States.
The iPhone is also available on various international carrier networks.
AT&T was the first carrier to officially offer the iPhone in 2007 beginning with its first generation model.
AT&T is a GSM network therefore it requires a SIM card for a phone to operate on its network.
On the iPhone, AT&T provides 2G / EDGE Mobile Internet as well as 3G Mobile Internet (*service availability based on network coverage for your area and may not be available in all locations.)
GSM networks such as AT&T allow users to access mobile data (Internet) while in a voice call without interruption.
AT&T offers tethering / mobile hotspot feature* (*official tethering service feature available with additional service fee and/or purchase of a qualifying data plan. See AT&T website for full information on plans and services.)
Verizon was the second carrier in the US to officially offer the iPhone. It is the first American CDMA carrier to offer the iPhone. The iPhone 4 and 4S models are available on Verizon Wireless.
Some CDMA iPhone 4S models have a SIM card slot intended for international roaming. It is not yet known if Verizon will offer official unlocking for overseas use.
Verizon operates on the standard EvDo 3G / 1x data network. The Verizon iPhone does not have 4G support. Verizon’s phones are not able to use data internet connection while in a voice call.
See the Verizon Wireless official website link above for more information about Verizon Wireless iPhone plans.
Sprint is the third American carrier to offer the iPhone 4S. Sprint is the latest carrier to officially offer the iPhone, leaving T-Mobile as the only American carrier to not offer the iPhone and US Cellular doesn’t count because they’ll never have any good phones.
Sprint is the only American carrier to offer completely unlimited data. However, the introduction of the iPhone to a carrier often causes a surge in data usage and directly affects the carrier’s network with slower data speeds for everyone on the network. When the iPhone comes to a new network data usage goes up, speed goes down. This often leads the carrier to introduce some sort of throttled, capped, or other limited data plans. Thanks to the iPhone Sprint may not see unlimited data plans for much longer.
Some CDMA iPhone 4S models have a SIM card slot intended for international roaming. Sprint has announced that iPhone customers with accounts in good standing can have their iPhone SIM card slots unlocked for use with an out of network carrier when overseas. In order to qualify for unlocking, iPhone customers must maintain their service for a minimum of 60 days.
For more information about the iPhone 4S on Sprint visit the official link for Sprint’s website.
Unofficial Support for T-Mobile USA
Unlocking the iPhone for use with non-supported GSM carriers is possible through Jailbreaking. iPhone Unlocking is most commonly known for reconfiguring the iPhone to operate on T-Mobile USA instead of AT&T. Using the iPhone on T-Mobile limits the data connection to 2G / EDGE which is much slower than AT&T’s normal speeds.
The latest “4S” iPhone model is powered by the same Apple A5 CPU chipset as the iPad 2. The iPhone specifically uses a dual core 1 GHz CPU.
The “optics” and camera has been completely redesigned, giving the iPhone the ability to record full 1080p HD video and photos at up to 8 MP.
The latest iPhone is known for Apple’s Siri voice control AI.
Siri is a voice controlled Artificial Intelligence program developed by Apple exclusively for the iPhone 4S.
Siri takes the place of the voice control feature found on previous iOS device models. If enabled in Settings, Siri is activated by holding the home button and is similar to how the voice control function is activated.
Once Siri is activated the user can ask the iPhone a question. Siri will proceed to contact Apple’s servers for a response. Siri also uses Google’s search engine for results from the Internet.
Siri Guide not listed yet on Ultimate Phone Guide. You can refer to Apple’s official documentation or Google for a complete list of example Siri commands and responses.
Jailbreak developers are attempting to port Siri to older generation devices that support iOS. The port would require a user to have propriatary files from an exsisting iPhone 4S. A tool to extract the files would most be developed. This is for legal reasons because closed source propriatary files cannot be redistributed. The iPad 2 would most likely be the first released device port of Siri. The iPad 2 and iPhone 4S both use the same A5 chipset, however a jailbreak for the A5 iPhone and IPad would need to be developed and released first. There is currently a working but unstable port of Siri for the iPhone 4 which is unreleased. This is all subject to change, soon, when progress is made.
This section contains information related to Apple’s iOS 5 software stack. Please see the original iOS 5 article
The iPhone 4S ships with iOS 5. The iPhone 4S and all other devices running iOS 5 can now be used without a PC. Since iOS 5 iTunes is no longer required to setup a device. iOS 5 has iCloud support which is a service that synchronizes user data with Apple’s servers. The data is stored with the Apple ID account. The data can be restored after a factory reset. The iPhone can now be setup directly from the device instead of using iTunes.
iOS 5 now supports Wi-Fi sync to iTunes over a local network if the user chooses to use iTunes.
iOS 5 can update its own firmware using OTA updates from Apple in the Settings.
Jailbreaking a next generation device requires a new exploit since the previous exploit (limera1n) is only compatible with older A4 devices (iPad, iPod touch fourth generation, and the iPhone 4)