High-Tech Ways to Keep
Your House Secure

Csilla and Tim Clark like to regularly go out for dinner and a show. But these days the show is their own living room -- beamed remotely onto their cellphones. From their home in Wenham, Mass., cameras send the couple live images and monitors send text messages when the house gets too chilly.

Home-monitoring technology is coming to your cellphone. And your BlackBerry. And your computer. The technology is pitched mostly as a safety and security measure. But it's also creating some obsessives who can't stop checking on everything from indoor thermostats to whether the lights are on in the kitchen.

In October, AT&T launched a $9.95 monthly service called Remote Monitor that beams streaming video from homecams to cellphones, and can send customized text-message alerts whenever there's movement in particular rooms. Companies such as QuietCare are capitalizing on the market for senior monitoring, creating elaborate programs that can email customers with updates on how many times their elderly relative visits the bathroom each day. Electronics retailer Best Buy is now selling a $15,000 home-monitoring system, ConnectedLife.Home, with features that include the ability to remotely turn on sprinklers or a washing machine.

Other makers include iControl Networks, which sells monitoring packages with wireless cameras and keychain remote controls, and WiLife, whose systems can be upgraded with night-vision cameras.

Johnny Wade of Lincoln, Calif., has interrupted weekend trips to his houseboat in northern California to get online and remotely adjust lights or rev up the air conditioner so his house is cool when he returns. Without the comfort of knowing all is well at home, Mr. Wade, 50, says he couldn't relax at the lake. "It gives us, more than anything, piece of mind."

Smaller home-monitoring systems are often sold as a package; users receive devices such as cameras, thermostats and motion detectors, along with an instruction manual. More elaborate setups, such as Best Buy's system, include professional installation. The market for home-monitoring systems is expected to grow from $91 million in 2007 to $400 million in 2012, according to Parks Associates, a Dallas research firm. For companies, this rising interest means having to dumb down tech-heavy systems so average people can use them.

Before AT&T launched its monthly service, the company tested a wireless camera by giving one to an employee with an engineering degree -- only to find that it took him three days to get it working. "We didn't think that was a good model," says Brad Bridges, associate vice president. The company includes only wired cameras, which are easier to install, in its system.

Much of this new technology has been driven by telephone companies as part of a broader push to use cellphones for more than just phone calls. A year ago, Sprint launched a service that lets parents track their kids on GPS maps on their phones or computer. Nannycams have also fed into the interest in home monitoring, with parents deciding they can do more than watch their children.

Now, other businesses are adapting home-monitoring features. Best Buy says real-estate agents track traffic through open houses by placing sensors on things like ovens, which shows the number of times they're opened. Robin Wilson Home, a New York company that pairs homeowners with contractors, now offers software that lets people watch their renovations from afar. Nursing homes are also offering families remote-monitoring systems, which can include daily detailed emails on elderly relatives' movements between rooms.

For some, it's purely escapist. Zach Glenwright spends most of his day editing video for a local news station. But every 30 minutes or so, he takes a break on his work computer to check on a camera of his own, monitoring the squirrels and birds in the backyard of his home in York, Pa. "It's kind of like watching a TV show," says the 25-year-old.

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