Amazon isn't the only retailer trying to get rid of the checkout line. Here's what others are doing

An Amazon Go grocery store in Seattle, Washington.
David Ryder | Bloomberg | Getty Images

You're already running five minutes late — but you desperately need a bite to eat. You swing into the nearest convenience store, grab a sandwich and walk right out.

Figuring out this type of in-and-out shopping experience was a major theme at this week's National Retail Federation convention in New York. The conference came one month after Amazon teased a futuristic convenience store that eliminates the checkout and will open to the public early this year.

The store, called Amazon Go, uses cameras and sensors to detect when an item is pulled from the shelf. Though the online seller has been mum on the details for how its store will work — or what it will cost — retail and technology experts concluded that the concept could be replicated by traditional retailers.

Yet with one of those firms estimating the cost to be millions of dollars per store, retailers are instead looking for ways to bring some of its attributes into the real world.

"We see much more effective solutions to getting to the same benefits," Brendan O'Meara, managing director of Microsoft's retail division, told CNBC.

One example is the Skip app, which was built on Microsoft's Azure platform. It allows shoppers to scan their groceries as they move through the store, and check out on their mobile device. Users are subject to an audit as they exit the shop, similar to what's done at Costco. However, the more shoppers accurately use the Skip app, the less likely they are to be audited.

Because this technology relies mostly on a customer's smartphone and a product's bar code, it costs "pennies on the dollar" to a fully equipped smart store, O'Meara said. Skip is being tested by Macey's, a regional grocery chain in Utah. The concept is similar to the Scan & Go technology being used across Sam's Club stores.

Check out Amazon's latest concept: A store without lines or registers

Everseen, an Irish technology firm whose original product was meant to detect scanning errors at the register, is now taking a similar approach to Amazon Go. It's launching a new product that
uses video cameras and sensors to track items as customers grab them from shelves.

Before shoppers leave the store, they'll receive a receipt on their phone. They'll then click a red or green button indicating whether the order tally is correct. From there, they can walk right out. Though Everseen declined to share exactly how much its 0Line technology will cost, it'll be a "fraction" of $1 million per store. 0Line will debut at Ireland's largest retailer in May.

In addition to technologies that cut out the register, there were others that, a la Amazon Go, provide insights on customers' shopping patterns.

Powershelf, which runs on Microsoft Azure, is one example. Powershelf uses sensors to inform retailers of out-of-stock items and about items that are consistently picked up and put back. Such data can help them better merchandise their stores, O'Meara said. Whole Foods uses Powershelf technology in 40 stores.

Regardless of which way retailers choose to go, there are challenges and limitations. Though cameras work well in a store of two people, "it gets fairly complicated" when there are 50 people inside, Brendan Witcher, a principal analyst at Forrester Research, told CNBC.

He added that an Amazon Go-type strategy would be difficult to roll out in a large store that sells bulky items. Retailers also need to figure out a way to make the systems secure. And finally, if customers have a question, they need to be staffed appropriately.

"Amazon's not trying to remove a person from a store. They're trying to remove the pain of checking out, and there's a big difference there," Witcher said.

The biggest challenge in deploying these types of technologies is the cost. IBM introduced the idea of a checkout-free store back in 2006, with a video of a man who appeared to be stealing. When the man was about to leave, an employee approached, and told him he forgot his receipt. A rollout of this technology never came to fruition because it wasn't a practical investment, IBM said.

IBM's version was based on radio-frequency identification, or RFID tags, which were the best existing technology at the time. But those tags were costly to include on packaging and to maintain and analyze. Even though the cost has been slashed from 30 cents to 10 cents over the past decade, according to Tyco Retail Solutions, they are difficult to apply to everyday grocery items like an individual apple or a head of a lettuce.

"This idea has been in the marketplace for a very long time," said Jill Standish, senior managing director of retail at Accenture. "Retail is pretty cautious about doing things unless they have a [return on investment]."

A more practical application of these technologies would be through a limited rollout in high-density markets, Standish said. There, the stores would cater to a crowd of time-crunched shoppers, and serve as a way to market the brand.

In the end, Witcher stressed that the biggest takeaway from these ideas is not whether they are viable today.

"The most important thing ... is that it takes us in the right direction for where retail needs to go," he said.

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