There's no way to tell the difference between Apple Inc.'s new iPhone 4S and the previous model. Until you turn it on.
In a week of using the 4S, I found so many new things under the hood that, with a few cosmetic changes, the company could legitimately have called it "iPhone 5" and no one would have blinked.
The speech-recognition capabilities are vastly better than on any other mobile device. The camera is much improved, not just in specs but in ease of use. And though the phone runs over 3G, or third-generation, data networks, it's faster than some phones that are being marketed as 4G.
The new iPhone -- available for order now and in stores on Oct. 14 -- is physically identical to the iPhone 4. In the US, it costs $199 for a model with 16 gigabytes of storage on a two- year contract, $299 for 32 gigabytes and $399 for 64 gigabytes. The phone comes with the new iOS 5 operating system, which I'll discuss in a future column.
The 4S runs on the networks used in the US by Verizon Wireless and Sprint Nextel Corp., as well as on those used by AT&T Inc. and most of the rest of the world. That's particularly important for Verizon and Sprint users who travel internationally and who won't have to worry about their phones becoming bricks outside the US
The most interesting new feature is Siri, the voice-recognition system. You've long been able to run searches on phones using Google Inc.'s Android software, and Microsoft Corp. has embedded speech-based features throughout the latest version of its Windows Phone 7 operating system. Those phones, though, have a limited vocabulary and often require you to phrase your inquiries very carefully.
Siri is something different. Remember the scene in the old "Star Trek" movie where a time-traveling Scotty tries to direct a Mac by picking up the mouse and casually speaking into it? Imagine it with just the mouse and not the Mac, and you've got the essence of Siri: natural language integrated with the phone's sensors and software.
When I asked Siri, "Will I need an umbrella tonight?" its robotic female voice informed me, "There's no rain in the forecast," while the screen displayed the weather report for my location. When I told it to find me a good Mexican restaurant in my neighborhood, it displayed a listing ranked by Yelp ratings.
No football scores
When Siri couldn't immediately provide an answer, as when I asked for the score of the San Francisco 49ers football game, it offered a Web search. You can also use it to make appointments, set reminders, dictate outgoing messages and read incoming ones.
Siri did occasionally trip up, sometimes because I confused it with homonyms or ambiguous phrasing. For example, when I asked it for "walking directions to 9 Lombard Street," it heard the "to" as "two" and provided directions to 29 Lombard instead. And when I was about to go outside and asked, "Do I need a jacket?" it presented me with directions to the nearest Men's Wearhouse.
Still, it's smart enough to be occasionally spooky, as when I simply told it to text "David" -- and it correctly deduced which of the 12 Davids in my address book I meant.
If not quite as awesome as Siri, the iPhone 4S camera is still as good as you're likely to find in a wireless phone, surpassing my previous favorite, the Nokia N8.
The headline number -- the increase in megapixels to eight from five -- doesn't tell the whole story. More striking is what's been done with the optics and software, including a larger lens aperture that lets more light hit the sensor, face detection and the ability to shoot video in full 1080p high-definition.
Sadly, the camera isn't able to turn a mediocre photographer into a good one. But I particularly appreciated the ability to take pictures even when the phone was locked, and that I could zoom in and out by pinching and zooming the image, far more intuitive in a touchscreen device than the former slider control.
The camera is also noticeably faster, thanks to the phone's new dual-core A5 processor, the same brain used in Apple's iPad 2. Indeed, the faster processor, combined with changes to the graphics, software and antennas, makes the iPhone 4S zippier across the board -- in launching and running apps and even in downloading data.
The 4S isn't a "4G" device, but my tests showed it to be as fast or faster on AT&T's network as phones being sold as "4G." (Verizon and Sprint users won't see that kind of performance, owing to those carriers' slower 3G networks.)
Using Ookla's Speedtest app, I compared the 4S with Samsung Electronics Co.'s new Galaxy S II, which AT&T labels as 4G. In dozens of tests in and around San Francisco, the iPhone 4S registered faster download speeds more than two-thirds of the time.
It achieved that performance without any apparent degradation in battery life. Apple says the new device provides up to 8 hours of 3G talk time, an hour longer than the iPhone 4. In regular though not constant use, I was able to go about a day and a half between charges.
The phone's new antenna design seems to have reduced the number of dropped calls over AT&T's much-maligned network, though my sample was admittedly limited.
With the iPhone's continuing advantage in number of apps (500,000 and counting), its arrival on the Sprint network and its ability to function as a world phone, the 4S doesn't leave many holes for the competition to plug.
And then there's this: The 4S is the first phone you'll ever be tempted to ask for the secret of life. Go ahead -- you'll get an answer, too. It isn't from "Star Trek," though science-fiction readers will recognize, and get a chuckle from, the response.
Rich Jaroslovsky is a Bloomberg News columnist. The opinions expressed are his own.