7-Eleven is launching a scan-and-go option at 14 stores in Dallas on Wednesday, with plans to expand it to other U.S. cities in 2019, in an effort to make the convenience store chain more convenient.

Customers use the new Scan & Pay feature in the chain's app and then scan in the merchandise they want to buy with their smartphones as they walk through the store, 7-Eleven announced Monday. It also connects with the 7Rewards loyalty program, so customers can find out about deals and promotions.

While items such as Slurpees and hot coffee are scannable using bar codes on different-sized cups, there are some products – such as hot foods, money orders and items that require age verification, such as alcohol, tobacco and lottery tickets – that still require human assistance.

More:Toys R Us' Geoffrey is back: His 'toy box' will be featured at Kroger this holiday season

More:Elon Musk: Tesla pickup will sport 'futuristic-like cyberpunk,' 'Blade Runner' design

More:After years of catastrophic losses, dairy farms are increasingly closing their barn doors

The Irving, Texas-based company’s chief digital officer Gurmeet Singh said this is a “convenience play,” a way to lure customers by enabling them to get in and out of the store faster, especially during peak morning and late-afternoon times.

"We’re always looking to innovate and disrupt," he said. "Customers are always on the go ... How can we make every 7-Eleven a breeze? How can they move in and out faster?"

7-Eleven built the prototype in five weeks, then spent months testing it at the employee store at the chain's headquarters in suburban Dallas, he added.

Ryan Hamilton, an associate professor of marketing at Emory University, said adding scan-and-go technology is a "major branding advantage" that could translate into more customers choosing 7-Eleven over another convenience stores, despite the limited amount of time they'll save.

"The biggest complaint about retail shopping is waiting in line and checking out," he said. "It's not going to matter that much, unless it's rush hour. Otherwise, you're in and out with your coffee in 90 seconds, but from a branding perspective, it is significant."

The news from 7-Eleven comes a week after Sam's Club announced it was opening a cashier-less store in Dallas, called Sam's Club Now. Scan-and-go technology will let shoppers use their phones to pay for merchandise they've selected. Also last week, Walmart revealed it's going to start letting customers avoid check-out lines by installing store employees in the aisles with credit-card readers to process purchases.

In September, Amazon unveiled its plans to open as many as 3,000 new checkout-free Amazon Go stores in the next three years. The first Amazon Go debuted at the company's Seattle headquarters in 2016 but opened to the public this past January.

7-Eleven has 67,000-plus stores in 17 countries, including 11,800 in North America, according to the company. More than 60 percent of stores are franchised.

Follow USA TODAY reporter Zlati Meyer on Twitter: @ZlatiMeyer