Just when you thought developers had exhausted the iPhone's potential to impress, here comes another: An application that promises to remotely unlock, start and warm your car from almost anywhere in the world.

Called Viper SmartStart, the app was launched earlier this week by Directed Electronics, a vehicle security and remote start systems designer, and can be downloaded for free from Apple's App store.

Using an existing remote car starting system from Viper, with a tap of a few buttons on your iPhone, your car can be started, warmed up and humming, just waiting for you to hit the road.

Although remote starting systems for cars usually have a limited line-of-sight range, Viper says its system has "virtually unlimited range" since your iPhone, not the original remote, communicates over cell networks with your car.

"We think customers will find all sorts of unique and personal value in Viper SmartStart," Mike Simmons, EVP of Directed Electronics' parent company, DEI Holdings, said in a statement. "Whether helping out her husband, who's locked his keys in the car, or securely locking her keys and purse in the car while she takes a jog with some music on her iPhone, we expect to hear about some uses we never anticipated."

Once the Viper SmartStart hardware is professionally installed in the car, the iPhone can also be used to defrost windows, cool down the vehicle in warmer weather, unlock the trunk or activate a panic alarm.

But though the app is free, the hardware that will actually make it work with your car is quite pricey.

The system will only work if paired with one of two Viper SmartStart systems that go for $499 (for those who don't already have a remote start system) and $299 (for those who do have remote start). The first year of service is free but, subsequently, service is $29.99 a year.

But this is just the tip of the iceberg. There are thousands of applications -- from the silly to the serious -- for wireless handheld devices.

Here is a sampling:

App Turns iPhone Into 'Sleaze Detector'

Sleaze ball or sweetheart? A new iPhone app claims it can help singles tell the difference.

Launched in September by information commerce firm Intelius, Date Check lets users perform instant background checks on potential dates from their mobile phones.

Once it's downloaded on an iPhone, the application only needs a name or cell phone number to search publicly available records.

If you activate the app's Sleaze Detector, it scans criminal records to determine if anyone with that name has been charged with drug possession, assault and battery, sex crimes, DUI and other offenses.

If you click Net Worth, it looks for information about home ownership and property value.

It can also check social networking sites, such as LinkedIn to provide employment and education information.

"Date Check is like having a private investigator in your purse," John Arnold, co-founder of Intelius and executive vice president of business development, said in a statement. "Letting a stranger into your life is a huge risk, and in the age of Internet anonymity, a simple online search isn't enough to tell you everything you need to know. "

This application, the company said, "gives singles a safer way to mingle."

But though the app itself is free, the services can cost up to $40, depending on the kind of searches that are selected.

Date Check is available for download in Apple's App store and will be available soon in Android and BlackBerry versions.

PUMA Index Tracks Stocks With Stripping Models

You've probably heard of the Dow, the S&P 500 and the NASDAQ 100. But try this financial index on for size: The PUMA.

To celebrate its new line of bodywear, sports clothing company PUMA launched an iPhone application earlier this month that tracks global stocks, but not in the way you might think.

As stocks on the Dow Jones industrial average go up and down, so does one key element on the PUMA models: their clothes.

"Think of it as an entertaining antidote to Wall Street woes," the company said in a statement. "So now if you lose your shirt, at least our models do too."

Though the application might make Federal Reserve Chairman Ben Bernanke blush, the models only undress down to their new PUMA threads. As the Dow climbs, the clothes come back on.

The PUMA application is free in Apple's App store, and the company says it can even help save consumers money. Showing the downloaded application to a PUMA sales associate can get you a 20 percent discount. That offer lasts until Nov. 8, 2009.

App Find Medicinal Marijuana Providers

Smoking marijuana is known to have an adverse effect on memory and concentration, but now, thanks to a new iPhone application, even the foggiest of users should be able to locate their connection -- make that medicinal marijuana provider -- with relative ease.

Launched by AJNAG (Activists Justifying the Natural Agriculture of Ganja), a Web-based community advocating for medical marijuana, the Cannabis app takes those seeking medicinal marijuana through the entire process of obtaining it. The app is downloadable from Apple's store for $2.99.

"Our goal is to put the power of cannabis change in your pocket while you enjoy the most sticky and potent iPhone application available!" the founders say in a statement on their Web site.

Here's how it works. The application displays an interactive map dotted with doctors who can prescribe medicinal marijuana treatment for their patients.

It also shows -- after, presumably, users have procured prescriptions -- the medicinal marijuana suppliers within the users' vicinity. And, what's more, the application includes a database of lawyers who specialize in marijuana-related cases, in should users encounter skeptical local authorities.

To help with grassroots media campaigning, the developers also say they will donate 50 cents for every "Cannabis" purchase to a non-profit reform fund, which they say will be set up once the application reaches 1,000 subscriptions.

Just remember -- Cannabis only works in states where marijuana has been legalized, so if you've scored tickets to a Grateful Dead show in, say, Alabama, don't expect Cannabis to help you score anything else.

Craving Pizza? Just Download the App

In a move sure to thrill its laziest customers, Pizza Hut unveiled recently its new iPhone application that allows users to order pizza without so much as dialing a number. Simply type in your order, then sit back and wait until it arrives.

For those bored with the traditional methods of ordering pizza, the app also has some unconventional tools. If you want extra sauce on your wings, for instance, you shake the phone like a bottle.

And, for those who find ordering pizza too sober a task, the app comes with a racing game named "Hut Racer."

Pizza Hut hopes the app will appeal to customers who rely on their iPhones, said Brian Niccol, Pizza Hut's chief marketing officer.

"As more of our customers are integrating the iPhone and iPod touch into their everyday lives, Pizza Hut wants to be right there with them," Niccol said in a statement. "As a longtime category leader in innovation, creating an App Store application is just one more way we are helping customers place orders in a way that best fits their mobile lifestyle."

Hard of Hearing? Just Grab Your iPhone

People don't normally equate the iPhone with medical innovation, but with the June release of an application that doubles as a hearing aid, they may have to reconsider.

The application, which is called soundAMP, is made by Ginger Labs, a California-based software applications developer, and is available in the iTunes store for $9.99.

Though it's not an actual hearing aid, soundAMP achieves a similar effect. Users just launch the application and then plug in a pair of earphones. The application takes in sound from a microphone (be it built-in, in a headset or from elsewhere) and then amplifies and filters it.

Then you can adjust the volume to your liking with a slider on the touchscreen. You also can replay five or 30 seconds by tapping the appropriate button on the screen.

Hearing aids often may be associated with the more mature, but soundAMP's developers insist their product is age neutral -- of equal value to the octogenarian hard of hearing and the college student stuck in the back of a large lecture class.

(As a caveat, if you really are losing your hearing, you should probably visit a doctor -- soundAMP may be novel, but medically certified it is not.)

RunPee Helps Moviegoers With Bathroom Breaks

Soda. Coffee. Water. Next time to you go to the movies, chug 'em all down.

As long as you have a new iPhone app by your side, you'll know when you can escape to the bathroom without missing the best parts.

Approved by Apple's App store in early July, RunPee (yes, really) promises to be the small-bladdered moviegoer's best friend.

The application features all the movies currently playing in theaters and tells users approximately how far into the movie each "pee time" begins, the cue line to listen for and even what they've missed. (When you're on your way back to your seat, you can hit a button to unscramble text that provides a short synopsis.)

"The idea came from watching King Kong the re-make in 2005," said Dan Florio, RunPee's creator, referring to Peter Jackson's marathon three-hour blockbuster. Throughout much of the movie, he said, he was desperate to relieve himself.

"I kept thinking, I wish they would just kill this ape so that I could get to the men's room," he said.

Like a good fan, he waited until the end, but not without noting a good three-minute sequence he could have done without.

"I just could have gone to the men's room during the scene and I could have enjoyed the end of the movie and the movie would have been better," the Orlando, Fla. developer said.

When he walked out of the theater and saw the lines of people waiting to get into the theater, he wanted to share his secret. But being a bit bashful, he kept it to himself.

The idea stayed in remission until August 2008, when he launched RunPee.com.

He said he's watched about 80 percent of the movies to scout out the best "pee times," but added his family has helped. And anyone who's interested can submit ideas to the site.

In January of this year, he partnered with brothers John and Sam Shahidi, and Cincinnati Bengals quarterback Jordan Palmer, to work on the iPhone app. Download figures aren't available yet, but Florio said traffic to the site has jumped from about 30 unique visitors a day last year to about 3,500 visitors a day.

Although the app is only available for iPhone owners in the U.S., John Shahidi said the plan is to expand to India, China and Australia.

Dunkin' Donuts Goes High-Tech

Thanks to the iPhone, coffee runs are now easier than ever.

In June, Dunkin' Donuts launched an application for the iPhone and Web that helps organize and automate group orders.

Using their computers and mobile devices, customers can initiate orders through 'Dunkin' Run' and alert friends and colleagues that they are willing to be the "Runner."

Each member of the group can add their order to the list and then the Runner can print the choices or use the iPhone to create a checklist so that when they get to the store, they don't miss anyone's order. The app doesn't yet transmit the order to the local donut shop.

"We conceived of Dunkin' Run as a social application that helps hard-working Americans stay slightly more productive," said Baba Shetty, Hill Holliday's Chief Media Officer. "It's based on the idea of reciprocity -- I'll get your coffee today and hopefully you'll get mine tomorrow -- in a way that perfectly complements the 'we're in it together' ethos of the Dunkin' Donuts brand."

Smart Phone Applications Keep You in Check

Booty Caller

So you're late again. You're a woman with a busy career but you're newly married and you have hopes for a family, too.

You're trying to get to a meeting when you hear the familiar ping of your cell phone, telling you a text message has arrived.

You open it: "Your fertile window opens today and lasts five more days," it says. "Stress can get in the way of conception, so relax and get a massage, meditate or take a yoga class."

The text you just received is from -- yes, this is its real name -- Booty Caller. The app is free, offered by a parenting Web site called BabyCenter.com.

Do you really want a text to remind you this might be a good time for sex? It may not be your idea of spontaneous fun, but its makers say it may well help you squeeze some fun -- and a new baby as well -- into an overscheduled life.

"Booty Caller is definitely a sign of the times," Linda Murray, the editor-in-chief of BabyCenter.com, wrote in an e-mail. Her site, she said, "set out to create a tool that would provide fertility information as well as tips on getting pregnant in fun, digestible text messages."

ScanLife

Look around -- through magazines, at store displays, on kids' T-shirts -- and you may see small, square black-and-white patches that remind you of bar codes. They serve much the same purpose. The idea comes from Scanbuy, a New York firm that hopes the little so-called EZcodes will become ubiquitous.

"We've been at it for a while," said Jonathan Bulkeley, the CEO of Scanbuy Inc., "and the idea's been the same: making it easier for you to navigate using the camera on your phone, instead of the keypad on your phone."

Point your camera phone at, say, an ad for running shoes, and your phone's screen will quickly show you a Web site with specs and user reviews. Point the phone at the code on a kid's shirt, and you're directed straight to his or her Facebook page.

Bulkeley said he can see countless other uses: How about a marker, for instance, on the wrapper for a head of lettuce that tells you how long ago it was picked from the field? He has even seen a code on a grave marker that lets you read about the life of the person to whom you're paying respects.

Financer

Picture yourself in the store, intrigued by the pair of running shoes you checked out via Scanbuy. But can you afford them?

Financer is a portable electronic ledger, a way for you to keep track of your money, no matter where you are.

"Financer is one of our most popular applications; and we've seen an increase in demand since the recession," said David Becker, CEO of its maker, dBelement.

The screen of your iPhone takes on the look of a checkbook ledger, the same thing you used a generation ago, except that it does the math for you.

Your account's a bit thin; maybe you'd better hold off on the shoes.

And ... Here's to Your Health

iFitness

So you can't afford those Nikes? For $1.99 (a lot of these programs have similar prices at the Apple App Store), iFitness will suggest workout routines to keep you in shape. Flabby arms? Touch "arms" on the menu and find the best exercises. Worried about your abs? The program will suggest a routine.

It will also keep you honest. You can keep a log of what you've done, get an idea of your progress and, if you don't like it, you can try Fit Phone.

Or, if you're like so many of us when it comes to New Year's resolutions, you can stop and feel guilty.

In which case, you may want to download ...

Fast-Food Calorie Counter

This is an app for those of us who choose to drown our sorrows with a burger and fries. Tap in any of 4,700 items from 41 chains and it will tell you the calorie count, amount of fat, number of carbs and everything else you need to know to go back and buy those running shoes. It's $2.99 via Apple from Concrete Software.

And last but not least...

Thousands of Apps Make Hectic Life a Whole Lot Easier

Breath-Test Device for your iPod, iPhone

Perhaps one of the more ambitious app/devices out there, iBreath is a breath-test device that attaches to your iPhone or iPod.

Users blow into the iBreath and a readout of their blood-alcohol content appears on the phone's screen.

"All kinds of people are using it," said developer Don Bassler, CEO of David Steele, the iBreath's manufacturer. "Parents of kids, college students, wives for husbands, boyfriends for girlfriends. The demographic starts dubiously as low as 16, but is basically the 18 to 50 crowd."

The iBreath debuted at Christmas and, according to Bassler, the company has sold thousands of the $79.99 devices.

Of course, even though we think these seven apps can go a long way in terms of making a hectic life a bit easier, mentioning these particular apps does not necessarily constitute an endorsement of them.

Each has many competitors, and you're invited to weigh in with suggestions in our comments section. Many apps have features you will love or hate, and the only way to find out for sure is to try them for yourself.

But most of the apps are either free or very cheap, which means a barrier has been crossed. There are a million things you can now do, with very little effort, on what you used to think was only your cell phone.

Unless, of course, you prefer to do them on paper, or a computer, or even -- what a quaint idea -- in the flesh.