NEW YORK ( MainStreet) — AT&T, T-Mobile and Verizon have bet many millions of dollars that you will want to do your shopping with Isis - a mobile phone based wallet - but here is the puzzler: Isis went live nationally last week and, so far, reaction among consumers and merchants adds up to a big yawn.

Does anyone care?

The draw is that with an Isis phone, you can pay at participating merchants - which includes any merchant presently capable of accepting contactless payments - and that means many McDonalds, Jamba Juice, Circle K, CVS, and a number of other national retailers. No need to swipe plastic to pay. Just use your phone and how cool is that?

Fact: some 24 million smartphones in the U.S. are Isis capable, said Jim Stapleton, chief sales officer at Isis. That basically means the phones are equipped with Near Field Communication (NFC) - a tap and pay technology - and that they run on Verizon, AT&T, and T-Mobile.

iPhone owners need not apply. Ditto for Sprint customers.

Isis shrugs off those absent players. "Every month two million smartphones are added to the total," said Stapleton - meaning that pretty much all new smartphones on the participating carriers ship with NFC.

Have a new phone, and it's easy enough to start on Isis. Download the app - at Google Play - and off you go.

Have a phone with even a little age on it, however, and even if it has NFC, you probably need to visit a store of your carrier to get a special SIM popped in.

If your phone doesn't qualify for Isis - around 40 models do, said Jamie Johnson, head of marketing at Isis - you are looking at buying a new phone, perhaps with no carrier subsidy. That could mean shelling out $500 or more.

And then what?

There's the rub.

Asked how many consumers had downloaded the Isis app, Stapleton declined to offer even a rough count.

By the count at Google Play, there have been 50,000 to 100,000 downloads of the Isis app for Verizon Wireless, a like number for T-Mobile, and only 10,000 to 50,000 for AT&T. Big those numbers may sound, but for the national launch of a purportedly cutting-edge payments platform?

The iPhone 5, by contrast, logged an estimated 2 million pre-orders in the first 24 hours it was available. Some experts peg opening weekend sales for the new iPad Air at over 5 million.

The Isis numbers look anemic by contrast.

"How many consumers even know about Isis," shrugged Greg Smith, an analyst at brokerage firm Sterne Agee.

He added: "It's tough to find optimism about Isis."

The other side of the pessimism is that - a handful of national retailers aside - to get significant acceptance of Isis at mid-sized and local retailers would require stores to upgrade to new terminals. That may happen as they face a 2015 deadline for accepting so called chip and PIN cards, aka EMV, or face penalties from Mastercard and Visa.