Just when the mobile-payments sector seemed to be settling down a little, another huge retail chain announced a new project. Wal-Mart (NYSE: WMT) is trying out a shopping and payment system featuring Apple's (Nasdaq: AAPL) iPhone. The new format is being touted as a way to enhance the customer's shopping pleasure by cutting down on lines, thus speeding up checkout times.

Mobile devices are catching on at major retailers
According to Reuters, the big-box retailer is testing a specialized iPhone app in Rogers, Ark. If successful, shoppers would use their iPhones to scan items as they shop and then transfer the scanned information to self-checkout kiosks, where shoppers would pay with their method of their choice. The article notes that while Wal-Mart is mum regarding future plans for the shopping and payment system, it would be a simple step to expand the format to all smartphones and segue into mobile payments.

Besides making the Wal-Mart experience even more wonderful, the new setup should save the store millions of dollars -- as it spends approximately $12 million in cashier wages each second, according to the store's CFO.

Other stores also use iPhones to speed up checkout and to allow staff to better assist customers. Stop & Shop has been using a similar iPhone-based system for more than a year, and Lowe's (NYSE: LOW) began equipping salespeople with more than 40,000 iPhones one year ago in an effort to update old technology. The iPhones allow staff to access information quickly, but they also serve as a point-of-sale system. The impetus for the upgrade was its closest competitor, Home Depot (NYSE: HD), which invested in Motorola devices for the same purposes a few years ago and has recently expanded the system to include more handsets per store. The retailer has also partnered with eBay's (Nasdaq: EBAY) PayPal for in-store payment processing.

Fool's take
This new configuration will certainly save Wal-Mart pots of money -- and probably garner more sales, since this method of shopping seems amenable to a higher rate of impulse purchases.

If Apple decides to wade into the mobile-payment market, this system would meld easily into that format. Wal-Mart definitely has mobile payments in its sights, having just announced its high-profile involvement in the Merchant Customer Exchange, a group of retailers that hope to mold the nascent digital payments sector according to its own formula.

As for Apple, any new retailer project that makes the iPhone even more ubiquitous is money in the overflowing Apple bank account. With all the big retailer interest in the iPhone, it's looking more and more probable that Cupertino will enter the digital-payments space soon. There's a big announcement planned for Sept. 12, and the fanfare could very well include iPhone-digital payments capability. Stay tuned.

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