Apple's latest iPhone doesn't look all that different on the surface from the iPhone 4 it replaces. But the iPhone 4S unveiled by Apple at a press event yesterday promises an improved processor, new wireless system, and more powerful camera, along with voice control capabilities.

The iPhone 4S is available in black and white, and will be released on October 14 in the UK, US, Canada, Australia, France, Germany, and Japan, on AT&T, Verizon, and newcomer Sprint. The iPhone 4S will be available in more than 70 countries by the end of the year, Apple says.

In unveiling the new iPhone, Apple senior vice president of worldwide product marketing Phil Schiller said that the iPhone 4S keeps the same Retina display, glass on front and back, and stainless steel band. Inside, however, it's all new: The iPad's A5 chip is now inside the iPhone - that's the Apple-designed, dual-core chip.

The iPhone 4S keeps the same Retina display, glass on front and back, and stainless steel band. Inside, however, it's all new: The iPad's A5 chip is now inside the iPhone - that's the Apple-designed, dual-core chip. Schiller says it offers graphics performance up to seven times faster than the iPhone 4, and CPU performance up to twice as fast. Schiller said that with the new internals in the iPhone 4S, "you really see it scream... in games."

The improved performance in the iPhone 4S doesn't come at the expense of battery life. Schiller said that for the first time on an iPhone, you can expect eight hours of talk time on 3G, 14 hours of 2G talk time, six hours of 3G browsing, nine hours of Wi-Fi, ten hours of video, and 40 hours of listening to music.

New wireless system

The iPhone 4S also sports a new wireless system. Schiller said that the phone can "intelligently switch between two antennas to transmit and receive," and the technology works even when you're on a call. The result? Better call quality, and faster download speeds.

The iPhone 4 could support 5.8Mbps up and 14.Mbps download speeds; the iPhone 4S offers 5.8Mbps uploads with 14.4Mbps download speeds. Schiller said that competitors describe those speeds as 4G, but that Apple is "not going to get into a debate about what's 4G and what isn't. The iPhone 4 came in GSM and CDMA models; the iPhone 4S comes in a single model that works around the world on both types of networks.

Camera improvements

The iPhone 4S's camera system gets a significant upgrade over the iPhone 4's, too, according to Apple. Schiller said that Apple "set out to create an all new camera," with the aim of challenging point-and-shoots. The iPhone 4S's camera offers an eight megapixel sensor, with 3264x2448 resolution. Said Schiller, "You can print out an 8x10 glossy photo that's pixel perfect." The iPhone 4S's rear camera offers 60% more pixels than iPhone 4's camera sensor. The new sensor is a state of the art CMOS backside illumination sensor, which affords 73% more light per pixel, which Schiller says means richer colors and better lowlight performance. The camera also takes pictures 33% faster than the iPhone 4.