American Express is doing a lot to shed its image as the card for the elite. In recent years Amex has worked with Twitter, Facebook, Foursquare, video game companies and other new partners to win the favor of young adults.

The 2013 Mobile World Congress in Barcelona, produced by the mobile operators group GSMA, was the launching point for many significant payments initiatives.

MasterCard Inc. today announced MasterPass, a digital wallet that supports mobile payments at the point of sale and online payments without the need to type a card number each time.

Today’s modern payment systems have their genesis in a number of older ventures that plied everything from the Web to biometrics to enable digital commerce. Some are gone, and some have evolved unrecognizably into their current form. Here’s a look.

Payment technology is gaining momentum and changing rapidly. More and more places around the world are adopting unique methods of payment.

Despite some glitches that are hampering vigorous adoption, the companies targeting mobile payments are finding success in forging brand connections. The problem is their connections are with narrow constituencies, and are often based on competencies beyond mobile payments.

Mobile wallets showcase many features that could transform the way consumers pay, but for many users the most appealing feature is the ability to make sense of all their receipts.

ShopKeep, which provides an iPad point of sale system, began supporting payments from SCVNGR's LevelUp loyalty and mobile payment system this week. One early adopter is already reporting success with the combined system.

The use of electronic payments can have a positive impact on national economies, with nearly $127 billion added to the U.S.'s gross domestic product (GDP) in the past four years, according to a study conducted for Visa by Moody's Analytics.

Visa's V.me digital wallet is picking up momentum and the initiative is "right on the point of the spear" of the card network's product development strategy, Visa says.

As many as 65% of the consumers testing the Isis Mobile Wallet are revisiting merchants often or taking advantage of mobile offers, an Isis executive says.

MACH, looking for a way to sell carrier billing services in the U.S. and expand in other markets, says it’s found the right partner in mobile payments company payvia.

What did mobile wallets look like before Apple and its peers invented the consumer smartphone market and launched App Stores to distribute systems like Passbook, Isis and Google Wallet?

Quick-response (QR) codes, the increasingly common square bar codes used in advertising and mobile payments, are stepping into new territory as a tool for bill payment.

The prepaid card provider Plastyc Inc. has added a mobile remote deposit capture feature that provides instant access to funds.

Mainstream consumers are still slow to adopt newer payment technology, but several cities are pushing ahead of the rest of the world.

Walmart and the other Merchant Customer Exchange members recently announced they would opt for a software-based mobile wallet instead of one based on Near Field Communication hardware. Is this a blow to NFC's future or does the technology have enough supporters to eventually change how people pay?

Many companies are trying to repurpose iPads as payment terminals. Leaf, a Cambridge, Mass.-based startup, instead created a commerce-specific tablet for small-business owners.

PayPal has won repeated partnerships with large merchants for its new point of sale payment system, but it paced itself with consumer adoption — a strategy the eBay unit seeks to change in 2013.

Research in Motion Ltd. received a significant stamp of approval for its software from Visa Inc. Visa has approved Waterloo, Ontario-based RiM's secure element manager software for Near Field Communication mobile payments.