Apple’s expertise in retail is being called on by Wal-Mart. The world’s largest retailer is looking to Apple to help it solve problems with its checkout process.

According to reports, Wal-Mart currently pays $12 million per second for its cashiers. In an effort to speed up and save month during the payment process, Wal-Mart has asked employees that own iPhones try out a shopping experience that allows them to scan items using their phone. Should the technology be introduced, customers could use their iPhone to scan items as they walk through the aisles.

The test does not allow users to pay via their iPhone, notes Reuters. The list of scanned items is transferred to a self-checkout kiosk, allowing shoppers to pay at that point. However, since there is no need to scan the items at that point the checkout process is faster.

Wal-Mart Chief Financial Officer Charles Holley said that pushing more shoppers to scan their own items and make payments without the help of a cashier could save Wal-Mart millions of dollars.

In a separate report, The Street speculated that Apple could kill off Visa, in a future where beside Visa and MasterCard logos you will start to see the logos of Apple and Google on the doors of your favourite stores. “The one thing consumers can't ever be without is their cell phones,” notes the report, suggesting that in the future credit card companies may have their work cut out convincing consumers that they should keep their cards with them at all times.

When people talk about the future of digital wallets - electronic smartphone-based replacements for credit cards, debit cards and cash - you're likely to hear the initials NFC in the same breath. NFC, for "near-field communication," is a set of technologies that makes it possible to pay for purchases using smartphones, among other things. There had beeen speculation that Apple would implement Near Field Communication (NFC) controllers in it’s next-generation smartphone, although recent reports have suggested that the technology won't make it into the iPhone 5

The idea is that all smartphones will contain special NFC chips that enable you to use your phone as a credit card. To make a transaction, you pass your phone over or near a special gadget that's hooked up to a cash register as an equivalent to swiping a credit card.

Many Android devices and other phones already have NFC chips. A few retail stores use NFC equipment. (As I write this, I'm sitting in a shop that's part of the Peet's Coffee & Tea chain. There's an NFC device near the register at the checkout counter, and there's a little sign specifying Google Wallet-based payments.)