The Isis mobile-wallet system has been around for years, but consumers have hardly noticed. That might be about to change. This week looks like a serious turning point for the stalled idea of mobile-wallet payments.

Isis was started by three of the nation's four largest mobile networks, including Dow (DJINDICES:^DJI) members and industry giants AT&T (NYSE:T) and Verizon. The idea is to let your near-field- communication-equipped phone stand in for your credit card, cutting down on wallet shuffling at the checkout counter. In the long run, purses and leather wallets might go out of style entirely if we move every function of cash and plastic into the mobile devices in your other pocket.

Isis

Will this smartphone app replace the plastic in your wallet? Image credit: Google Play.

But users needed to pair their Isis-enabled smartphones with a supported credit card from Barclays, CapitalOne, or Discover, which limited the service's success. These are hardly market leaders in America.

But in the last couple of days, two more Dow members raced to Isis' rescue. This time, it was financial powerhouses American Express (NYSE:AXP) and JPMorgan Chase (NYSE:JPM), both of which added Isis support to some of their most popular consumer credit cards.

Chase and American Express handle orders of magnitude more card transactions than the other alternatives, so this is a major breakthrough. It's also tied to a national rollout, replacing the regional test markets where Isis has been available so far.

Is this the push that brings mobile wallets into the mainstream? Well, it takes more than just some big-name support from the banking and carrier sides. You also need a handset with near field communication, or NFC, to transmit the payment data to the checkout systems.

So far, that leaves Apple (NASDAQ:AAPL) out of the equation. NFC circuitry has not yet been added to iPhones, and the limited success of mobile wallets so far kind of justifies Apple's decision. There are several nationwide NFC-based payment systems in use today, but there are no huge success stories to share. For example, Google is cutting features off its Google Wallet service, and that mobile-wallet system might not survive Big G's next spring cleaning.

But it's also a chicken-and-egg problem: Would mobile wallet services like Isis suddenly explode if Cupertino baked NFC chips into iPhones? If the upcoming iPhone 5S adds NFC chips later this year, we'll get a real-world test of that theory.

And maybe we just love our plastic cards and leather wallets too much to ever leave the wallet at home. With the heft and brand recognition of four Dow components behind it, Isis is about to challenge the old swipe-and-sign model in the real world.

Fool contributor Anders Bylund owns shares of Google, but he holds no other position in any company mentioned. Check out Anders' bio and holdings or follow him on Twitter and Google+.

The Motley Fool owns shares of Google and Apple. Motley Fool newsletter services have recommended buying shares of Google, Apple, and American Express. Motley Fool newsletter services have recommended creating a bull call spread position in Apple. Motley Fool newsletter services have recommended creating a write covered straddle position in American Express. The Motley Fool has a disclosure policy.

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