Attendees at Apple's Tuesday announcement of the iPhone 5S and 5C crowded into a hall to get their hands on the new phones for a few minutes and try them out. Here's a roundup of some of those first impressions, almost universally favorable for both handsets.

iPhone 5C, the lower-cost iPhone

Compared to the now-discontinued iPhone 5, the main differences in the 5C are: a plastic body wrapped around a reinforced steel frame; bright colors; an improved front-facing FaceTime HD camera; and slightly larger battery. It's also somewhat heavier: 4.65 ounces versus 3.95 ounces for the iPhone 5. It's available only in 16G- and 32-GB models; no 64-GB storage.

The plastic phone's feel is getting good marks.

"Remarkably solid and dense, more like a candy-lacquered metal phone than a plastic phone," say CNET's editors. "The 5C has a steel frame under the polycarbonate, and the smooth finish feels very hand-friendly. Hopefully it'll stay scratch-resistant. The curved edges are a bit of a return to the older plastic iPhones, but the phone's squarer design still comes through: it has a flat back."

[FIRST LOOK:Apple iPhone 5S & 5C]

The glossy finish is "not the fingerprint magnet that we've come to expect on other devices," says Engadget's Brad Molen

Camera, buttons, ports "are all in the same place," he says. The one change: "instead of two sets of speakers flanking the lightning port, the 5c features only four individual holes lined up to its right."

With the same A6 chip as the iPhone 5, the 5C "performs terrifically, and looks fantastic," says Darrell Etherington, at TechCrunch

"I'm maybe most impressed by how light and yet solid the iPhone 5C feels," he says. "While it may not quite live up to the ultra-luxe metal and glass feel of the iPhone 5 and now 5[S], it doesn't feel like a cheap device; this is a premium phone, despite the price tag and somewhat older internals."

"The 5c is almost like a toy, a rugged, comfortable device that doesn't feel much heavier than the iPhone 5 despite being noticeably larger," says David Pierce, writing for The Verge

"If you're going to make a plastic phone, though, this is how to do it. From the cohesive shell to the smooth and glossy back (which did pick up a fair number of fingerprints) the device feels far better than Samsung's or LG's plastic options."

Importantly, the 5S's year-old A6 processor handles iOS 7 just fine. "iOS 7 ran smoothly, and the camera was if anything faster than normal -- though part of that is surely the new camera app in iOS 7," Pierce wrote.

"It was fast launching apps and didn't have any problems handling a preloaded photo gallery, taking pictures using the new iOS7 camera app or anything else I did with it," says Martyn Williams, IDG News Service. "In short, it felt zippy."

Apple apparently paid a lot of attention to making the plastic body "feel premium."

"It's not a cheap-feeling phone, but it doesn't have the same premium finish as the 5S," says Slashgear's Chris Davies. "There's something a little toy-like about it, though not in a bad way; it's solid and dense, and creak-free, and the weight is evenly balanced along the length."

AnandTech's Brian Klug says he's "impressed with how the 5C ends up feeling in the hand."

"What's interesting about the 5C is really the way its rounded corners all seem to have the same radius, which gives it a very unified feeling in the hand," he says. "The front, edge, and sides all share that same rounded profile. It still retains the same overall profile as the iPhone 5 as well. Buttons on the 5C are clicky and responsive, and also have that same hard coated feeling without feeling cheap. That's really the important thing about the 5C: it had to be solid while still being made out of polymer, something OEMs in the Android space still haven't quite nailed down."

iPhone 5S: the new flagship

The iPhone 5S incorporates the industry's first 64-bit processor for a smartphone, an improved main camera and software, and integrated fingerprint scanner in the home button. It's also available in two new anodized aluminum colors: gold, and something variously described as black, graphite and space gray.

"In the hand the iPhone 5S feels much like the iPhone 5, with the 7.6mm depth and 112g weight giving a lightweight yet premium experience," says Luke Peters, writing for The Mirror. "Button and hardware placements also replicate that of the iPhone 5, with the only change being an improved flash on the back and the Touch ID [fingerprint] sensor that's built into the home screen.

Setup for the fingerprint scan was "very straightforward." The new camera "seemed to take noticeably crisper pictures than the iPhone 5 and iPhone 5C," Peters says.

The performance is stellar. "The new processor is blazing fast, apps open in an instant, video content is free from judder, image-processing (we tried processing shots in the photo app) is perceptibly faster than the iPhone 5," he says. "Content just zips along in iOS7 and anyone making the jump from an iPhone 4S to the iPhone 5S will notice a huge difference in speed and power."

He viewed a demo of the new Infinity Blade III video game "and the graphics looked simply outrageous."

AnandTech's Klug has a similar response to the 5S performance. "[P]laying around with a few games and especially Apple Maps with 3D buildings manages to feel even faster," he says. "I'd say in Maps with flyovers especially the 5S feels amazingly fast and doesn't hitch or stutter at all."

The new camera flash system, which now has two different color temperature flashes which juggled to balance the color temperature of the scene being photographed "looks to be a substantial improvement," according to Klug.

"This thing is way speedy, presumably because of the jump to 64-bit," says Jordon Crook at TechCrunch. "We only poked around the OS a little, but everything we saw was buttery smooth."

Apple seems to have created a fingerprint sensor that is highly accurate and very simple to use. "In our initial tests, the fingerprint detection works almost shockingly well," Crook says. "Setup takes seconds, and it worked consistently and instantly thereafter. After configuring a 5s to be on the look out for Darrell's fingerprint, Greg's fingerprint was immediately turned away. Once I added mine to the system, it worked immediately. There was literally zero frustration."

IDG News Service's Williams says, "I've used fingerprint sensors on phones and PCs before and the experience was bad enough that I always switched them off." 

"On the iPhone 5S, it's very easy. In fact, the toughest part was registration, which requires users to repeatedly press their finger on the home button, so the software can scan and gain enough data about the fingerprint," he explains. "It took about 15 seconds to accomplish. Once done, opening apps was easy. With the phone locked, it literally took just a touch to unlock and jump to the home screen....Unlike my previous frustrating experiences, the fingerprint lock should make it faster and easier to get into your home screen while keeping it secure from others."

The Verge's Dieter Bohn added a couple of observations about the new home button. "[I]t's now made of sapphire so that it can act as a reliable fingerprint reader," he writes. "It's not nearly as concave as previous models -- in fact, it's almost flat. Luckily, it still maintains a nice, tactile feel when you click on it and we don't foresee anybody running into any issues."

Bohn wasn't able to stress test the new camera, but he did see improvements. "If Apple's claims about improved [camera] processing and larger-sized pixels on its sensor pan out, the iPhone 5s, like its predecessor, will have the best smartphone camera for the average user on the market," Bohn writes.

John Cox covers wireless networking and mobile computing for Network World.Twitter: http://twitter.com/johnwcoxnwwEmail: [email protected]

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