(NEW YORK) -- The iPhone 4S, which was unveiled the day before Steve Jobs died, is hitting stores -- and is being shipped to those who ordered it online -- Friday.
Here are five things that will be helpful to know if you're an Apple enthusiast unpacking your new phone or waiting for it to come:
Powerful New Phone, But Not a Game-Changer
Apple made a careful, rational decision to upgrade the existing iPhone 4 instead of selling a shiny, mouth-watering -- and potentially buggy -- iPhone 5, said analyst Ross Rubin of the NPD Group.
"The iPhone is a five-year-old product now, and Apple has had success finding a design that works," said Rubin, who writes a technology column for ABC News. "By allowing it to be offered on Sprint and selling older models at a lower price point, it's increasing its market share."
So the 4S has the same body as its predecessor -- but its innards are significantly changed. It has a more powerful processor -- the same dual-core A5 chip that runs the iPad 2. And its eight-megapixel camera is unusually good for shooting in low light.
Siri Will Answer Your Questions Now
The iPhone 4S answers questions and takes voice commands through an "intelligent assistant" called Siri. Apple says Siri is smart enough to know that if you ask, "How's the weather forecast?" or, "Do I need my umbrella?" you're really after the same thing.
Of course, the phone still has a touch screen with virtual buttons you can touch.
Apple's iCloud feature is not actually part of the phone -- but that's the idea. The hot trend in computing is to store data in the "cloud" -- on the Internet instead of only your laptop or your handheld. If you saved that document on your computer back home, you'll now be able to check it on your phone, or iPad, or somewhere else without trouble.
Some Wall Street analysts have pointed out that iCloud, at least so far, has fairly limited capacity. But it's a start.
An OS is just an operating system -- the basic software that keeps something running -- so what's the big deal about Apple's iOS 5? It's a big enough deal that people crowded online Wednesday to download it and had a good deal of trouble when they tried.
Apple lists 200 features -- such as a "notification center" that combines your emails, reminders, texts and tweets; and "iMessage," a texting system that gets you around those annoying data charges from cell phone carriers.
For all the buzz Apple gets, and for all the loyalty many people have to their iPhones, it's not the market leader. In the U.S., smartphones that run on Google's Android software have 44 percent of customers, according to the research firm ComScore (iPhones have 27 percent). Worldwide, BlackBerry is most widely used.
But Apple has cornered the market for cool. The seamless marriage of design and function -- that was Steve Jobs' mission. The iPhone 4S was the last Apple product announced before he died, though there are reports Jobs left behind detailed plans for products for years to come.
The new model drew almost twice as many online orders in its first weekend as the iPhone 4 in 2010.
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