LOS ANGELES — As a Cobra attack helicopter pilot, Marine Capt. Jim "Hottie" Carlson was running support missions above Afghanistan last summer when it occurred to him that it was taking far too long to find where U.S. troops were under attack.

"Do you have any idea how long it takes to find the right map, unfold it and find where you're going? It's agonizing," he said.

Frustrated that he had to flip through dozens of maps stuffed inside his chopper, Carlson, 31, loaded the documents onto his personal iPad, enabling him to zoom in, zoom out and quickly move from one map to another.

Carlson's brainstorm shortened the time it took to pinpoint a location from "three minutes to about 30 seconds," he recalled recently, and it soon helped change the way the military is thinking about warfare. The Marines now have more than 30 iPads in cockpits across their fleet of helicopters and fighter jets.

For soldiers in the 21st century, iPads, iPhones, Androids and other smart devices could eventually be as common on the battlefield as helmets, canteens and rifles.

Seeing an opportunity, software companies and defense contractors are developing mobile applications that will enable soldiers to pass along intelligence, view reconnaissance images or even pilot small drones by remote control.

This high-tech handheld revolution, of course, opens the military up to the same problems that everybody else with a smart device faces — security threats and concerns about dropped service. The Army is using iPhones, Androids and BlackBerrys in mock wartime situations in New Mexico and Texas.

Such devices are coming in handy in simulated security raids and checkpoint stops to take pictures of Arabic writing and gather biometric data, such as fingerprints and iris scans, McCarthy said.

The troops are also testing about 95 mobile applications, or apps, designed to help soldiers perform specific tasks with their cellphones.

One app is dubbed Soldier Eyes. "Imagine that you're dropped in an unknown location on a moonless night," said Michael McCarthy, who leads an effort by the Army to test smartphones for use on the battlefield. "You open this app and through its GPS coordinates, it shows you where you are. It shows you where your adjacent units are."

It can also provide cumulative information about the region, he said, showing how many roadside bomb attacks have occurred and when they took place.

The app is being developed by Overwatch Mobile Solutions, a subsidiary of Textron, in close collaboration with the Army.

"A typical soldier carries a map, a compass, a radio and a GPS," said Evan Corwin, a senior program manager at Overwatch. "This enables them to have all of that on one device."

Harris Corp. of Melbourne, Fla., has developed a miniature cell tower mounted on a Humvee that provides cell coverage to remote areas with patchy or nonexistent service. The system, named KnightHawk, generates connectivity by providing network signals for a three-mile radius.

"Troops aren't typically dropped in an area where AT&T and Verizon have coverage," said Edward J. Zoiss, Harris' vice president of advanced programs and technology. "That's where Harris comes in."

Harris has also developed an app called Eyes-on-Target that enables troops to share streaming video on their phones — rather than use radios and hand and arm signals.

Even drone aircraft may get a boost from these phones. Students at MIT and researchers at Boeing have demonstrated that a person can fly miniature drones with an iPhone.

In all, the Army said it has spent about $4.2 million over two years to develop the apps and test smartphones. The Air Force and Navy also have pilot programs testing smart-device technology.

But the devices are risk-prone and susceptible to security breaches that could threaten military secrets. The widespread adoption of mobile devices is likely to bring about "an explosion" of attacks, said a recent report by the Internet security firm McAfee.

"The military is opening themselves up to serious problems," said Chris Soghoian, a privacy and security researcher at the Center for Applied Cybersecurity Research at Indiana University. "It seems stupid to use a platform that thousands of people are trying to hack."

Storing data on the phones will end up disclosing military information or showing the enemy precisely where the troops are through the devices' GPS transmitters, Soghoian said.

If the Army was to decide to put a smartphone in the hands of every soldier, it alone would need to buy 1.2 million phones. That could be a major source of revenue for phone makers.

In the coming years, defense giant Raytheon anticipates that the app market will be huge. The company, famous for building 2,000-pound bunker-busting bombs and Tomahawk cruise missiles, will unveil an online store called Appsmart this year where military apps can be bought.

Commercial apps typically sell for a couple of dollars because they often sell by the millions. With far fewer made, military apps are expected to be more expensive and could sell for as much as $500 apiece, said Mark Bigham, Raytheon's vice president of business development for defense and civil mission solutions.