10/24/2012 02:27 pm ET Updated Dec 24, 2012

Is It Time to Use a Mobile Wallet?

You may have seen it. You're standing in line at McDonalds, Starbucks, Home Depot or a local store, and the person in front of you waives her phone at checkout then walks out with her stuff. No cash, no card, just a waving phone.

That person in front of you is one of the 12 percent of Americans (according to the Federal Reserve) paying with a "mobile wallet." Chances are good she is using a service from Google, PayPal, Square or Starbucks. You can expect to see more and more mobile wallet payments as companies start using the Passbook service in Apple's IOS6 to distribute coupons and bar codes that you can redeem at certain stores, and as more stores back ISIS, the mobile payment joint venture backed by AT&T, T-Mobile, and Verizon Wireless, which rolled out October 22.

Mobile wallets are full of promise because they are always connected to the Internet and they know where you are (thanks to the geo-location feature of your smartphone), so they could have cool features. Wouldn't it be great to have an app that warns you if that new TV you covet is beyond or within your budget, or one that that pings you with local coupons for a store you're visiting or one that lets you share restaurant deals with friends in the neighborhood?

Sounds good, right? So is it time to toss your faithful leather wallet and go mobile?

I don't think so, and here's why. So far the promise remains a promise; none of the apps I mentioned are available. Mobile wallets are just another way to pay with no substantial benefit over cards or even cash.

And there are some drawbacks. There are competing vendors, each with their own partnering stores. No one system has emerged as a standard, so a mobile wallet that works at Starbucks may or may not also work at Target.

In addition, tying your wallet to your phone has risks. What if, like me, you are among the 70 percent of people who do not use a password to lock their mobile phone and you lose it? Or what you don't lose it but the battery needs a charge? Or what if the phone falls in a puddle and stops working? Also, I've yet to hear about using mobile wallets getting cash at the ATM.
Until there's a mobile driver's license, you'll need to carry a wallet anyway, so you might as well carry some plastic as well and wait until mobile wallets mature a little.

That said, if your bank or card provider offers a free mobile banking smartphone application to manage your account on the go, jump on it. Mobile banking apps are not like mobile wallets: they will not let you wave your phone to pay in the checkout lane, but they will let you stay on top of your budget on the go.