Thieves are increasingly going after iPhones and other "smart phones" but victims now can fight back with technology.

One device allows a user to remotely activate a loud siren designed to rattle the thief. Another application, designed for iPhones, can reveal the phone's location.

Police statistics show petty crime is down in New York but anecdotal evidence and recent headlines about street muggings targeting costly and coveted devices like Apple's iPhone and T-Mobile's Sidekick have disturbed smart phone users concerned about protecting access to e-mail, passwords and other data.

"When we have seen spikes in thefts, a significant portion has to do with ... highly desirable products," said police spokesman Paul Browne. "In the last couple of years it's been iPods, Sidekicks, iPhones."

He said most of these muggings involve teenagers robbing other teenagers and take place on subways in the afternoon after schools get out.

New technology helps owners of expensive gadgets to get them back after they are lost or stolen. The Find My iPhone feature from Apple, which declined to comment for this story, enables users to determine the phone's location and erase the data on it, among other things.

A Chicago blogger who tried the feature after his iPhone disappeared tracked the phone's movements from a friend's computer. According to his post at http://happywaffle.livejournal.com/5890.html, he got his phone back -- and a handshake from the surprised culprit.

"You're lucky you didn't get shot in the face," read one comment on the blog.

MAKE A DEAL WITH PHONE THIEF

Indian company Maverick Mobile Solutions' system allows victims of theft to activate a siren and send a text message to the phone -- perhaps to offer a deal to get the phone back.

Fear of a gadget-related crime wave is not new. In 2005, as Apple's signature white earphones were becoming ubiquitous in U.S. cities, the New York Police Department reported an increase in subway crime linked to iPod thefts. Before that, victims were targeted for their expensive sneakers.

But cell phone theft is a particular concern because of the risk of identity theft, said City Councilman Peter Vallone.

"It's bad enough losing your phone and that's all it was a few years ago," Vallone said. "Nowadays, if you lose your phone, you can very quickly lose your identity."

Local media have reported spikes in iPhone-related street muggings. In May, a thief snatched actor Kevin Bacon's Blackberry on a New York City subway platform.

Many iPhone users agree that, given the amount of personal data stored on phones, losing one could be devastating.

"The damage would be extensive," said Joshua Deutch, 32, a freelance IT consultant. He said he would "not think twice" before wiping data -- including bank account numbers and multiple passwords -- if someone stole his iPhone.

But Deutch said pursuing a thief would be going too far.

"Obviously, there's some excitement with that but I have insurance," he said. After data has been wiped clean, the iPhone is "just a brick," he said.

Some thieves get caught due to missteps.

In March, a man stole a woman's iPhone on a Manhattan subway platform and then used it to snap pictures of himself. He e-mailed the pictures to his personal e-mail address, inadvertently using his victim's e-mail account, according to the the New York Post newspaper.

The victim saw the photograph in her own e-mail outbox and alerted police, who checked the picture against mug shots and then identified and arrested the thief.

Still, many smart phone users say they do not worry about someone getting hold of their personal data.

"A lot of people are really uptight about anyone knowing anything about them," said Nick Divers, 23, who has not taken steps to protect the data on his iPhone. "Is that a big deal? Not to me."