Wal-Mart Stores Inc is testing a new "Scan & Go" self-checkout system, powered by the iPhones of customers, in an effort to improve in-store shopping for consumers while simulataneously cutting costs for the big-box retailer.

Last month, Walmart announced a variety of initiatives aimed at improving the customer experience, keeping prices low, and reducing company overhead. In response to frequent complaints about long lines and unattended registers, the company promised to increase the number of self-checkout kiosks available to shoppers in each store. The company also announced a partnership with Target, Best Buy, and a number of other retailers to create a new mobile payment network. The new company, called Merchant Customer Exchange, aims to provide brick-and-mortar consumers with the same one-touch purchasing options available to the customers of eBay or Google.

Now, Reuters reports Walmart is testing a "Scan & Go" self-checkout system, with the help of iPhone-owning employees at a supercenter near company headquarters in Rogers, Arkansas. In an unverified email, allegedly sent from Walmart Labs to employees, the company asked that staff also bring interested friends and family members to the event. To boost interest in the test, Walmart offered $100 cash and a $25 gift card to those who took part, according a now-hidden survey on the Survey Monkey website.

For about an hour, testers scanned and bagged their groceries while walking store aisles. Once finished, they transferred the contents of their virtual shopping cart to a self-checkout kiosk, and paid for their items using the existing self-checkout payment process. Though many expect the addition soon, the company did not offer a mobile payment option during the test.

Walmart plans to add the "Scan & Go" feature to its existing iPhone app, a relatively small application that currently allows users to create shopping lists and check store inventory before leaving the house. If successful, the smartphone powered self-checkout process could help shave some of the $12 million Walmart spends each second to cover the cost of cashiers' wages in U.S. stores.

No word yet on whether shoppers can expect "Scan & Go" to make the leap to Android or Windows Phone in the future.