The map rift with Google may not be Apple's biggest misstep with the iPhone 5. Instead, it might be the company's decision to exclude near-field communication (NFC). Most major smart phone–makers—including Samsung, Nokia and HTC—are backing the technology for its ability to turn their devices into mobile wallets, with which users can make purchases and digitally store boarding passes and coupons. As phone-makers, retailers and credit card companies work out the feasibility of NFC as a gateway to facilitating commerce, others see the technology as opening doors—literally.

NFC-enabled smart phones can function like the badges that many people swipe en route to their offices every morning. A key difference between NFC and the radio-frequency chips embedded in employee ID badges is NFC's two-way communication capability, making it a more versatile tool for security.

Two companies are testing how NFC might improve employee access to their facilities: Good Technology, which sells mobile data security software, and Netflix, the subscription-based entertainment content provider. The California-based companies recently wrapped up several-week-long pilot programs with HID Global, a provider of ID security technology, to see whether it makes sense to replace employee building-access photo badges and key fobs with NFC-enabled smart phones. A small sample of employees received Samsung GALAXY S III handsets loaded with an app that automatically confirmed their identities at NFC-enabled security checkpoints.

NFC uses electromagnetic radio fields to allow two devices to exchange data in either direction when passed within four or five centimeters of one another. Radio-frequency identification (RFID), by comparison, works from several meters away, but information moves only unidirectionally—for example from an E-ZPass tag on a windshield to a tollbooth reader.

Although much larger and heavier than photo badges, the GALAXY phones used at Good Technology and Netflix ostensibly would provide increased security because they can be PIN-protected—if the device were lost or stolen, the average person without hacking skills would not be able to access information stored on it.

"Having an authentication credential on a phone is more secure than a badge or another physical access token because the only security I have on that is my picture," says Michael Mahan, Good Technology's senior vice president of special markets. "If I lose my badge, someone else could fairly easily pick it up and use it to get past security."

As part of the test project, Mahan also equipped his own office with an NFC-enabled lock to control access when he was traveling. In addition to allowing Mahan to grant office access to specific employees remotely, he could also pull data from the NFC system that showed who had used his office, and when.

At both companies most of the employees liked the prospect of simply waving a smart phone over an NFC reader so much, they said they would be willing to load the app on their personal handsets if they could not get shiny new GALAXY phones from their employers. More than 106 million NFC-enabled Google Android phones shipped in 2011, according to research firm IHS iSuppli. NFC support can in some cases be added to a smart phone by installing an NFC-compatible SIM card or microSD card.

Although both Good and Netflix plan to extend NFC testing to additional employees, some concerns remain, including whether adding the NFC app to someone's personal smart phone would prematurely drain the battery if the app is left on for an extended period of time. NFC is designed to use only a small amount of energy, but a smart phone with a dead battery would defeat the purpose of using the device as a security badge—or anything else.

Apple has not left its customers out in the cold when it comes to short-range communications that might someday be used for purchases or security. Instead of NFC, the company has (since the debut of its iPhone 4S in 2011) endorsed Bluetooth 4.0, which includes a low-energy version of the wireless radio technology that is a bit slower than NFC but has a much greater range (about 50 meters). The new iOS 6 mobile operating system features a new app—Passbook—designed to use Bluetooth LE (low energy) for data exchange. As with NFC, the key challenge now is getting retailers and other businesses to develop apps as well as buy readers and other equipment that can take advantage of the technology.