San Francisco - Geeks aren't the only people wearing Google Glass.

Among the people testing Google Inc's wearable computer are teachers, dentists, doctors, radio disc jockeys, hair stylists, architects, athletes and even a zookeeper.

Some 10,000 people are trying out an early version of Glass, most of them selected as part of a contest.

To get a sense of the advantages and drawbacks of the device, The Associated Press spoke to three Glass owners who have been using the device since late spring: Sarah Hill, a former TV broadcaster and current military veterans advocate; David Levy, a hiking enthusiast and small business owner; and Deborah Lee, a stay-at-home mom.

Glass is designed to work like a smartphone that's worn like a pair of glasses. Although it looks like a prop from a science fiction movie, the device is capturing imaginations beyond the realm of nerds.

The trio's favourite feature, by far, is the hands-free camera that shoots photos and video through voice commands. (Images can also be captured by pressing a small button along the top of the right frame of Glass.) They also liked being able to connect to the Internet simply by tapping on the right frame of Glass to turn it on and then swiping along the same side to scroll through a menu. That menu allows them to do such things as get directions on Google's map or find a piece of information through Google's search engine. The information is shown on a thumbnail-sized transparent screen attached just above the right eye to stay out of a user's field of vision.

Among the biggest shortcomings they cited was Glass' short battery life, especially if a lot of video is being taken. Although Google says Glass should last for an entire day on a single battery charge for the typical user, Hill said there were times when she ran out of power after 90 minutes to two hours during periods when she was recording a lot of video.

Glass' speaker, which relies on a bone conduction technology, also is inadequate, according to the testers the AP interviewed. They said the speaker, which transmits sound through the skull to allow for ambient noise, can be difficult to hear in any environment other than a quiet room.

"If you are out in the street or anywhere else where there is any noise, it's impossible to hear," Lee said. "That has been challenging because there is no way to adjust it. If you could adjust the sound, I think it would solve a lot of problems."

Hill, 42, a resident of Columbia, Mo, became a Glass evangelist shortly after she picked up the device at Google's New York offices in late May. As the AP watched her get fitted with Glass though a video feed on Google's Hangout chat service, Hill quickly began to rave about her ability to take hands-free pictures and fetch information from the Web simply by asking the device to get it. "This is like having the Internet in your eye socket," Hill said. "But it's less intrusive than I thought it would be. I can totally see how this would still let you still be in the moment with the people around you."

The liberating aspects of Glass came into sharper focus for Hill as she took a cab to the airport for her flight back to Missouri. During the taxi ride, she began a video call on Google Hangout with people living in Austria, the United Kingdom and St. Louis. As the cab was preparing to drop her off at the curb, Hill was about to end the call so she could carry her baggage. Then came her first Glass epiphany.

"That's when it hit me that, Holy cow, I don't have to cut the call off," Hill recalled. "I could continue talking because I didn't have to hold a phone. So I carried on a conversation through the airport and people were staring at me like, 'What is that thing on your face?'"

Hill became accustomed to the double takes and quizzical looks as she wore Glass to community gatherings, restaurants and shopping excursions. The encounters usually led to her offering others to try on Glass, and most were impressed with their glimpses at the technology, Hill said.

"When you have these glasses on, it's like it helps you see the future," Hill said. "It helps you see what's possible."

Hill, a former news anchor and reporter for KOMU-TV in Columbia, Mo, believes Glass is destined to transform broadcast journalism by empowering reporters to capture compelling images at scenes without the need for cumbersome equipment. She likens it to having a satellite TV truck that only weighs 1.5 ounces. Glass also would make it easier for reporters to field questions from viewers through the Twitter app or through direct texts.

Hill has already used Glass to provide a tour of the World War II memorial in Washington, DC, for veterans gathered in St. Louis by Veterans United, where Hill now works as the group's chief storyteller. The veterans were too old or ill to make the journey themselves, so Hill gave them a close-up look through a video feed transmitted through Glass in June.

Lee, a New York City resident, has been relying on Glass mostly to capture precious moments with her 9-month-old daughter, Maddie. Her favorite moment came when she photographed some of her daughter's first giggles a couple months ago. Lee, 34, told Glass to take the pictures as she as tickled and kissed her daughter's tummy.

"Obviously, you can't do that with a phone in your hand, so I am totally loving Glass," Lee said. "It has really been great."

Glass also allowed Lee to set up live video sessions with her parents in Oregon so they could see Maddie eat her first solid food just as she saw it. She also took pictures of her raising Maddie airborne that wouldn't have been feasible with a camera requiring hands-on operation. "I am capturing all these tiny moments that are really exciting with a baby," Lee said.

Unlike Hill's experience in Missouri, hardly anyone in New York gives her a second look when she wears Glass in Central Park or around her neighborhood.

"I thought more people would stop me in the street or something like that, but that hasn't really happened," Lee said.

Levy, 39, rarely wears his Glass around his home town of Boulder, Colorado, because he doesn't want to stand out from the crowd. Just two days after Levy picked up the device in New York, he recalls seeing someone else wearing the device at the airport. "My initial reaction was, 'What a jerk,'" Levy said. "There was a little bit of ostentatiousness about it, as if he were flaunting it. I am a low-key guy who doesn't like a lot of attention. I have an iPhone that does a lot of things that I might otherwise make Glass do if I didn't want to make a spectacle of it."

Glass has impressed Levy while wearing it for his main purpose of taking pictures and video of some of the trails charted by Protrails.com, an online hiking site he co-owns. His objective is to share more of the Continental Divide with schoolchildren in hopes it will inspire them to do more outdoor exploration and less sitting at home.

"I was wondering if Glass would feel like a burden or part of my hiking equipment. It actually feels pretty cool," Levy said. "They are totally fine on my head and don't block any of my view. When you see something interesting, you can immediately have a camera on it. I really enjoy being able to capture those images."

Glass' ability to take hands-free pictures and video has raised concerns among privacy watchdogs who believe the device will make it easier to secretly record the activities of other people. But Levy is convinced that what Glass can do isn't much different than what many people already do with their smartphones. To prove his point, Levy used his iPhone to record a conversation he was having with a friend who was railing against the privacy risks posed by Glass.

"I recognize that Glass can make people uncomfortable, but I have to say the privacy issues are a specious concern," Levy said. "If I have a phone in a restaurant, I can get a picture of just about anybody I want with it. So what's the difference between a phone and Glass?"

Lee regularly has Glass with her when Maddie is around other babies and said she hasn't heard any privacy objections from other parents. That could be because she has been careful about following the social cues around her. If she sees other parents snapping pictures of their babies with their phones, Levy has donned her Glass. If no one else is taking pictures or video, though, she leaves Glass in her bag.

Some analysts question whether Glass will have mass appeal once it hits the market. Skeptics who have seen the early participants walking around wearing Glass believe the device will eventually be remembered as a geeky curiosity that never lived up to its hype, similar to the Segway, the two-wheeled, self-balancing scooters that remain an anomaly more than a decade after they first went on sale.

Angela McIntyre, a research director for Gartner Inc., believes the retail price for Glass will have to plummet to $200 to make a significant dent. Early testers had to pay $1,500 for the device, though Google hopes to bring that price down by the time of its mass-market release next year.

Even then, McIntyre believes smartwatches, another type of Internet-connected device starting to appear on the market, will win a bigger following than Glass. "Most people are just more used to putting technology on their wrist," she said. "It's less intrusive and obtrusive to wear a watch that can serve as a second screen to your smartphone."

In a recent report on wearable computing, Forrester Research analyst Sarah Rotman Epps predicted Glass will appeal largely to "young, socially connected tech optimists" and professionals, such as surgeons, construction managers and even farmers, who could use the device as part of their jobs. She defines tech optimists as people "who see technology playing a positive role in their lives."

Hill figures it's still way too early to envision all the different ways that Glass will be used.

"We are guinea pigs using the Model Ts of a new age in computing," she said. "They don't have heated seats or radios or all the amenities that they will eventually, and we are still learning how to drive them."