CNN News:智能手机的防盗功能

Smartphones can do a lot of things: they can make calls, we can text, surf the Web, it can also make us a target. Cell-phone theft is increasing in cities around the country. We are not talking about somebody stealing the phone out of your bag when you`re not looking. We mean stealing it right out of your hand.Situation has some people calling for actions.

This surveillance video shows a woman getting robbed of her cell phone while in the middle of a conversation. A crime so common, that type in "cell phonetheft" on Youtube, and you`ll find tons of surveillance video of people having their phones ripped off.

San Francisco`s police chief says in many cases users are asking for trouble.

Think if you took $300 out of the ATM machine. You wouldn`t walk down the block for several blocks counting the 20s.

The problem is becoming so rampant that it`s estimated that stolen devices cost consumers $40 billion a year. So pressure is mounting for cell-phone carriers and the device makers to figure out a way to deter theft.

San Francisco District Attorney George Gascon wants to see a so-called kill switch on phones.

So that when they get report it`s stolen, they could be render inoperable.

He accuses the industry of dragging its feet to what he calls a technological solution.

Every time that a phone gets stolen, we go back and we replace it for him. So the carrier gets to make another sale, the manufacturer gets to make another sale, and the profit just continue to be.

The nation`s largest carriers, though, are getting more aggressive. Now, participating in a new nationwide database for stolen phones to prevent them from being activated. But critics say it`s yet to have a meaningful impact, because stolen phones often wind up overseas and fetch more dollars.

The late model iPhone ranks here, just down the street from here can bring about $300. If it gets exported to Latin America or Asia or Africa, it can bring in as much as seven to $1000.

But is a kill switch even possible? We went to arguable the leading mobile security company in the world, Lookout, which makes a popular app for Smartphones.

The notion of just being able to render a phone useless. Can that happen?

It`s technically plausible. A phone is just a computer. If you destroy the - an operating system the phone relies on, the phone can't be used.

So, if it`s technically possible, why isn`t that happening?

Because it`s not a very easy thing to do.

Now, Apple`s iPhone does have a feature that will track stolen phones and erase the data, sometimes more valuable than the phone itself. Lookout has a similar feature for phones using Google`s android. But the point, according to critics, is the entire industry needs bolder thinking.