The big upgrades with the iPhone 4S are internal. The iPhone 4 wasn't a slow device; in fact, it felt faster than most rival smartphones with much faster processors, thanks to Apple's complete top-to-bottom control over the operating system, including the user interface. But the iPhone 4S is much quicker than the iPhone 4 with most tasks, and it offers up to seven times the graphics performance of the iPhone 4. Apps now open instantly, the Web is even speedier, and gaming has a notable performance increase.
Apple touts the 4S as is the first smartphone to incorporate two antennas and the ability to switch between them even while on a phone call. Plus, it's a true world phone for Verizon and newcomer Sprint, which for the first time is offering the iPhone 4S and the previous-generation iPhone 4. In short: Apple took the best smartphone, from a hardware and design perspective, and made it even better.
NEXT: iOS 5