It allows her to send e-mails, text messages, instant messages and surf the Web. She can also make phone calls, but that's a function she never uses.

Vazquez-Hernandez, 19, is deaf.

She is part of a niche market of technology users who buy smart phones such as the Sidekick II and the Blackberry, not just for fun but as a means of communicating with each other and connecting to the hearing world. The Sidekick II is so common in the deaf and hard of hearing communities that it even has its own hand signal in American Sign Language (two palms held together and opened like a clam shell).

"To the hard of hearing and deaf community, it is a big boost," says Jeff Newton, a consultant for public safety at the Lane Independent Living Alliance or LILA. "This kind of technology offers us more options."

While a celebrity such as Paris Hilton might use a Sidekick II to, say, send a nasty e-mail to her former friend Nicole Richie, the device has a much more practical purpose for someone such as Vazquez-Hernandez. She uses her phone to communicate with her boss, family and friends.

"If someone can't get a hold of me, they can e-mail or text me," she says.

Vazquez-Hernandez also can send outgoing messages. And using a service called Internet protocol relay, or IP relay, which has been available to computer users for years, she can communicate on her Sidekick with anyone who has a land line or cell phone. Similar to the text phone, or TTY service, used for years on home phones and pay phones, IP relay allows her to send typewritten words to an operator who repeats them to a caller on the other end of the line. The caller's words are translated back into text for Vazquez-Hernandez to read.

If you can imagine being unable to order a pizza, call a friend or make an appointment for a haircut without using a special text telephone, advocates say, you'll have an idea of how a device such as the Sidekick can help make life easier for someone such as Vazquez-Hernandez.

Or, says Linda Diaz, a LILA coordinator and co-president of the group Self Help for the Hard of Hearing, imagine being stuck along the side of the highway with no way to call for help.

"I think they're absolutely necessary for people who can't hear at all," Diaz says. "If a deaf person is in an emergency situation, what do they do without that Blackberry or Sidekick?"

Sarah Hafer, a deaf graduate student at the University of Oregon, used her Sidekick to call for an interpreter when she was in a car accident in New Mexico. Without the device, she says, she would have had to wait for the police to arrive and call an interpreting agency.

"I was terribly fortunate to have my Sidekick," says Hafer, who purchased the first generation Sidekick in 2002.

Before the Sidekick came along, a deaf person in need of help would have had to use a two-way pager to call a friend or walk to the nearest TTY equipped pay phone. But as pay phones have become more scarce, so too have TTY pay phones. This makes mobile communication devices even more important, advocates say. "In my opinion, the most important (device for a deaf person) to have is a Sidekick II," says Vazquez-Hernandez, who also uses a desktop computer and a video phone to communicate from home.

The Sidekick II is not the only technological communication device used by the deaf and hard of hearing. Video phones allow users to speak in real time using American Sign Language and specially designed cell phones provide greater compatibility with hearing aids.

"(These devices have) provided communication parity for a population that hasn't had much parity," says Annette Leonard, an outreach coordinator at Western Oregon University.

Leonard, who helps employers make workplaces more user-friendly for the deaf or hard of hearing, uses a Motorola smart phone to communicate with her clients. Her cell phone, like the Blackberry, will do many of the same things as the Sidekick II, but the Sidekick remains the most popular choice among most of the people she works with, she says.

Zach Tenhaeff, a retail sales representative with the T-Mobile Direct store in Eugene says nearly half the Sidekicks he sells are to deaf or hard of hearing customers.

Even before the first Sidekick came out, there was strong interest in the device among the deaf and hard of hearing communities, says Jeff Folino, senior manager of the Sidekick for T-Mobile USA. When it came time to redesign the phone, the manufacturer, Danger, Inc., saw an opportunity to cater to the estimated 28 million Americans who have suffered some degree of hearing loss. The second generation Sidekick, which debuted in mid-2003, featured a more powerful vibrating message alert, two free IP Relay applications and greater compatibility for users with cochlear implants. The phones' popularity, users say, is also due to the fact that it is easy to use and it carries a lower price tag than many phones offered by competing service providers. Sidekicks sell for about $250 plus a $30 monthly service charge.

T-Mobile, which is the sole service provider for the Sidekick II, gives special training to its sales agents, instructing them on how to best communicate with shoppers who cannot hear. Tenhaeff keeps a pad of paper handy and he has learned to tell when his customers are reading lips.

"I was telling a co-worker that I should learn a few words in sign language," Tenhaeff says. "We get so many (deaf) customers."

By Lewis Taylor