The iPhone 5.

A week following the launch of the iPhone 5 and iOS 6, Apple CEO Tim Cook apologized for the company's imperfect new Maps app. But flawed maps haven't been the only issue to get some consumers worked up in the three weeks since they got their hands on Apple's latest smartphone.

Though overall and demand remain high, some customers fret about a variety of problems - from intolerably slow hang times when email is loading, to frustrating battery life.

A survey by On Device Research of nearly 16,000 users in the U.S. last month revealed a slight decrease in device satisfaction among those who upgraded to iOS 6 compared with when they upgraded to iOS 5.

All this has to be taken in perspective. sold more than 5 million iPhone 5s over the first weekend. More than 100 million people have downloaded iOS 6 onto older models of the iPhone or on their . Even if a teeny percentage of problem units turn up - and some are inevitable - the are sure to register. Folks are rarely blase about Apple. You're often either a passionate devotee or outspoken critic.

Veteran Apple watcher Leander Kahney, who runs the Cult of Mac website, has seen it before. He says some of the current issues bring to mind "Antenna-gate," when some users complained of a weak signal on the iPhone 4. The late tried to appease customers with free cases. Apple "gets a real drumming in the tech press," Kahney says. But that drumming comes, he says, only after many of these same people go ecstatic over Apple's latest and greatest. "There's a germ of a problem, a germ of an issue, and it gets blown out of crazy proportion. Apple gets overpraised. They suffer from overcriticism."

Some concerns that have surfaced:

-Purple haze: The camera on the iPhone 5 has garnered mostly positive reviews. But some users have noticed a purple haze or flare on some of the pictures captured when the phone is angled toward a bright light that may be just outside a scene. This is not atypical. Tests conducted by Consumer Reports revealed that this Jimi Hendrix effect is not limited to the iPhone 5.

Apple, meanwhile, posted the following resolution online: "Most small cameras, including those in every generation of iPhone, may exhibit some form of flare at the edge of the frame when capturing an image with out-of-scene light sources. ... Moving the camera slightly to change the position at which the bright light is entering the lens, or shielding the lens with your hand, should minimize or eliminate the effect."

-Battery. Apple claims up to eight hours of talk time for the iPhone 5, and eight to 10 hours of Internet use, depending on whether you're using 3G, LTE or Wi-Fi networks. But some people haven't fared so well.

There are, well, a battery of possible explanations. People might actually be using the phone more. The battery could be taxed in the first day or so of usage, when you're syncing a lot of stuff and downloading content. If you're in an area with a weak network signal, the radios inside the phone may be working harder to make a connection.

-Scratches. In an email exchange reported by 9To5Mac, Apple Senior Vice President Phil Schiller responded to a customer who had seen "some scuffs, scratches and marks" on his device. Schiller wrote, "Any aluminum product may scratch or chip with use, exposing its natural silver color. That is normal." It's been recently reported, though, that such dings are causing quality control crackdowns at Foxconn Technology, which assembles the iPhone, leading to possible supply shortages.

-Screen glitches. Are bugs inhabiting some iPhone 5 displays? In the "Green glow on iPhone 5 unlock screen?" topic area in the Apple Support Communities, one user wrote that a green glow appeared around the edge of the display on his iPhone for a fraction of a second after you turn on the screen. Some users reported similar issues.

YouTube videos are documenting another screen problem, a constant flicker of light that appears under the keyboard on some devices. Apple hasn't publicly weighed in on these issues.

-Slowness. Some users have experienced painfully slow times between when they tap on a message in an e-mail inbox and when that message actually appears.

Wi-Fi woes have been another problem. Apple has already offered a fix for owners of the Verizon iPhone 5 that addressed a problem in which the device tapped into cellular data when the phone was connected to Wi-Fi.

Whatever problems are emerging aren't affecting sales. Consider the issue that has gotten the most media attention: Maps. Despite CEO Cook's apology and the snags surrounding Maps - inaccuracies, missing points of interest, etc. - a survey released Friday by ChangeWave Research indicated that the Maps app is "irrelevant" when it comes to demand for the new iPhone.

And 90 percent of those surveyed who already have tried Maps on the new iPhone or on another iOS 6 device reported no problems with the app. Only 3 percent characterized it as a "very big problem." Maps "is not an antenna issue," says Paul Carton, ChangeWave's vice president for research.

Adds Cult of Mac's Kahney: "The vast majority of consumers are totally delighted with the and iOS 6."

Apple declined to comment.