When it comes time to pay, retailers may scan a bar code on the phone, consumers may tap their device on a reader or they may do nothing at all as the register and phone communicate automatically using near field communication technology. Regardless of the method, consumers are often free to go their way without swiping a card, entering a PIN or signing a receipt.

According to a 2012 survey conducted by the Carlisle & Gallagher Consulting Group, 48 percent of respondents expressed interest in mobile wallet technology. Not surprisingly, younger consumers between the ages of 18-50 and those in households earning more than $50,000 a year were most interested in these mobile apps.

Mobile payments mean more money spent

Although mobile wallets haven't caught on to the same extent as, say, texting and tweeting, that hasn't stopped retailers and payment processors from seeing dollars signs when looking to the future.

Technology consulting firm Gartner was reported in CNN Money as estimating mobile payments will be a $617 billion market in 2016, compared to $171.5 billion in 2012. In addition to an overall increase in the amount of purchases being made via mobile payments, retailers can also look forward to more spending from consumers using contactless methods.

MasterCard Advisors discovered spending increased an average of 30 percent in the 12 months after an individual first used a contactless payment. For those in the highest spending category, that's $600 more a month that shifted to contectless payments.

Retailers and credit card companies compete for market share

Mobile wallets have attracted the attention of businesses large and small. Some retailers, such as Dunkin Donuts and Starbucks, have launched mobile wallet apps specifically for their stores. Others, including the Google Wallet app, allow users to load multiple credit cards that can be used at a variety of stores both online and in-person.