"Developers don't have to change their apps," said Milanesi. "They will, of course, take advantage [of the larger screen] when they create their next versions. But you can buy an iPhone 5 today and not feel all of a sudden that thousands of apps are suddenly not relevant."
Apple used that same strategy in 2010 when it launched its first iPad, making it possible to run iPhone apps on the new, larger-screen tablet.
Inside, the iPhone 5 relies on an Apple-designed A6 chip that Schiller said was approximately twice as fast as the A4 in last year's model. Apple revealed no details about the A6, however, such as its clock speed and the number of cores it contains.
The iPhone 5 also supports the faster LTE data networks operated by some carriers worldwide. In the U.S., Verizon has the largest LTE network. "It just screams," Schiller said.
"After the Samsung trial, Apple has addressed the two things that people love about Samsung phones ... they have larger screens and LTE," said Moorhead. "Well, look, Apple just rolled out a larger display and LTE."
Powering the iPhone 5 is a larger battery that Apple rated at 8 hours of both talk time and browsing over 3G, as well as 8 hours of browsing using LTE. The talk time number is identical to the 4S, but 33% more on 3G browsing. Apple claimed the iPhone 5 runs 225 hours in standby mode, 12.5% longer than the iPhone 4S.
A new connector -- smaller by 80% -- replaces the 30-pin port that the iPhone has relied on for the last five years. Schiller dubbed it "Lightning," a play on its "Thunderbolt" display and storage connector brand available in newer Macs.
During today's event, Scott Forstall, Apple's head of iOS development, demonstrated several new features of iOS 6, the mobile operating system that powers the iPhone 5.
Apple's own mapping technology takes a bow in iOS 6, and for the first time, includes turn-by-turn directions, said Forestall. Other improvements he cited ranged from a full-screen mode in Safari that takes advantage of the new 4-in. display, photo streaming to other iOS devices, and Passbook, the company's ticket and boarding pass manager.
Siri, the voice-activated digital assistant that debuted a year ago in the iPhone 4S, has been enhanced, Forstall said as he demonstrated her new-found skills at locating restaurants and movie theaters.
None of the Apple executives mentioned NFC (near-field communications), the technology that lets mobile device owners wave a phone over a short-range wireless receiver or tap the device to make a purchase, or bring a pair of compliant devices close to each other to transfer data or sync content.
Analysts earlier today mentioned NFC as a possible part of the iPhone 5 intro, but concluded that the technology wasn't ready for prime time, or worth Apple's interest at this point.
But there were lots of improvements experts were ready to highlight, among them those in Siri, camera enhancements, better noise suppression and a new directional microphone system.
The last two seemed aimed straight at Siri.
"They not only jazzed up Siri, which I think is more popular than the press thinks, but the microphone and noise suppression changes are there to improve the experience with Siri," said Gottheil.
Milanesi echoed Gottheil. "If Siri can hear me better, that's important," she said.
Apple also launched a fifth-generation iPod Touch that closely resembled the iPhone 5, with prices ranging from $299 for a 32GB device to $399 for a 64GB model.
The iOS 6 upgrade -- which will be available to owners of iPhone 3GS, iPhone 4 and iPhone 4S smartphones, as well as the second- and third-generation iPads and the fourth-generation iPod Touch -- will debut Sept 19, two days before the iPhone 5 reaches customers.
"There are two types of buyers, those who care about specs and those who care about experience," said Moorhead. "Apple expertly addressed both. They upgraded what they needed to upgrade to stay competitive and improved the differentiators that are Apple's hallmarks."
Gregg Keizer covers Microsoft, security issues, Apple, Web browsers and general technology breaking news for Computerworld. Follow Gregg on Twitter at @gkeizer, on Google+ or subscribe to Gregg's RSS feed . His email address is gkeizer@computerworld.com.
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