Apple’s new killer app, Apple Pay, may indeed someday change global commerce for good.

That day isn’t here yet, however. Three days after launch, my experiences with the NFC-based payment / tap-to-pay system show that Apple Pay is still very, very beta. At this point, you may find yourself using it barely, if at all.

Available only on the new iPhone 6 and iPhone 6+ running iOS 8.1, you will not be greeted with any calls to action to set up Apple Pay. You’re on your own to find it in Passbook or Settings, although configuration – when it works – is straightforward.

Only two of my seven credit and debit cards in my physical wallet worked in my virtual wallet. The "take a photo to scan your card" feature worked successfully on the card numbers, but not on the expiration dates. The rest of the process was smooth and intuitive.

The cards that don’t work make Apple Pay pretty limiting. While one of my Chase cards worked, another two were not supported. Nor was anything from U.S. Bank or Target. My American Express card worked right away. At the bottom of this blog post is a list of cards that are accepted and not accepted. You may have more luck than I did.

In the real world, my experience today was sloppy, at best. Not many retailers accept Apple Pay yet, but Walgreens and Radio Shack supposedly do, so I strolled over to the Grand Avenue mall to try it out.

At Walgreens, I asked the clerk if the store accepts Apple Pay. "I honestly don’t know," she replied, having no idea what I was talking about. I told her I’d try it, anyway, so I held my iPhone 6 up to the credit card scanner, put my finger on the home button, and five seconds and two tries later, my purchase of Starbursts Minis went through as if I’d made a regular credit card purchase.

I stopped at Radio Shack next. I’m not a fan of this place, anyway, and today didn’t change that. I picked out a cheap iPhone case and took it to the register. I asked the clerk if she accepted Apple Pay. I might as well have asked if the store accepted Euros or Yen, because she was utterly confounded by my question. She called her manager on the headset, and he didn’t know, either. Ultimately, she said they don’t, so I left.

That’s a little different than Radio Shack’s corporate line on Apple Pay:

"As part of our commitment to put customers first, we want to provide additional payment options that take advantage of new solutions and make the process easier for the customer," RadioShack CEO Joseph Magnacca said in a released statement. "We are pleased to continue to leverage technology to improve our store experience."

It’s different, too, than what U.S. Bank said when the technology was announced, on Sept. 9:

"We are thrilled to be part of this historic moment with Apple," said Richard Davis, chairman, president and chief executive officer of U.S. Bancorp. "As we focus on U.S. Bank’s future, we will continue to grow our mobile technology in order to keep pace with the current and next generation of banking customers, and anticipate how to make our products and services more convenient. Working closely with Apple to bring Apple Pay to U.S. Bank customers across the country aligns with our legacy of simplifying customers’ lives, developing exceptional banking products and services, and our ability to make cultural connections with current and future customers through the utilization of technology in innovative and practical ways."

So, yes, Apple Pay does work. Kind of.

If you can find a credit or debit card that is compatible, and then if you can find a store that has been properly trained – or you’re willing to teach yourself – it works great.

Until then, Apple Pay isn’t ready for prime time. And this is considering that it was delayed a month after the iPhone 6 and iPhone 6+ were released. I don’t know how to call it anything other than another botched release by Apple. Like Apple Maps, but with your money.

I mean, does it "just work?" Not by a long shot. Yet.

But when the kinks are worked out, Apple Pay could be very cool and convenient – and I’ll use it all the time. When that is, however, is anyone’s guess.

List of accepted/not accepted cards from MacRumors.com (user names in parentheses):

ACCEPTED DEBIT:
Bank of America Debit
Chase Debit Visa
Chase Business Debit Visa
Chase Visa Platinum Debit
Citibank Debit MC
Wells Fargo Visa Platinum Debit

ACCEPTED CREDIT:
American Express Blue Cash Everyday (Rogo117)
American Express Blue Cash Preferred
American Express Business Plum Card (Goldnose)
American Express Business Gold Card (Small Business)
American Express Centurion Card (Goldnose)
American Express Delta SkyMiles
American Express Delta SkyMiles Business Credit Card
American Express Costco TrueEarnings Credit Card (T-Will)
American Express Credit Card
American Express Everyday
American Express Optima
American Express Platinum
American Express Green
American Express Premier Rewards Gold
American Express Starwood Preferred Guest
American Express Zync
Best Buy MC - Citi (jbachandouris)
Bank of America American Express (mosi76)
Bank of America - Cash Rewards (tyler23)
Bank of America Bank Americard Rewards
Bank of America MasterCard - Outdoor Rewards
Bank of America - World Points
Capital One MasterCard
Capital One QuickSilver VISA
Capital One Visa (topher227)
Chase (Visa only)
Chase Disney Visa
Chase Freedom
Chase Liquid
Chase Marriott Rewards Premier (Black Card)
Chase Slate
Chase Sapphire Preferred (won't scan w/ camera)
Chase Southwest Airlines Premier Visa
Chase MileagePlus Club
Chase MileagePlus Explorer
Chase Presidential Plus
Citi
Citi AAdvantage Executive Platinum MC
Citi - Best Buy MC (jbachandouris)
Citi - Double Cash
Citi Diamond Preferred Mastercard
Citi Simplicity (Rogo117)
Citi Forward Visa
Wells Fargo Visa (britney spears)
Wells Fargo Visa Platinum Debit/Credit
Wells Fargo Private Bank By Invitation Visa

NOT ACCEPTED DEBIT:
Ally Bank Debit (topher227)
Associated Bank MasterCard/debit
BB&T visa debit
Charles Schwabb Debit
Citizens Bank Visa Debit (jayiw)
Corning Credit Union Visa (txa1265)
First Tech Federal Debit (Krevnik)
Fifth Third Debit (xultar)
Navy Federal Debit ["Later this Fall"] (Krevnik) November per e-mail from NFCU (oddnendz)
North Carolina State Employees Debit
Regions Bank - Coming soon (Lifesuxbad)
Santander (formerly sovereign) debit
Simple Visa debit (awhitmer83)
Suntrust Debit
San Diego County Credit Union VISA Debit (hyperliteg4)
Target Debit (hyperliteg4)
TD Bank Debit Card Coming Soon (Xiph0s)
Union Bank Debit Card
U.S. Bank Visa Debit (darkflounder)
USAA Debit [Due Nov 7th] (Lloydbm41)

NOT ACCEPTED CREDIT:
American Express JetBlue (Rogo117)
American Express Macy's Credit Card (stephen1108)
American Express Serve
American Express Corporate
Amplify Credit Union Master Card
Banana Republic Visa Credit Card
Bank of America Business
Barclaycard (piratep)
Barclay Arrival+
Barclays Bank US Airways Dividend Miles Master Card - "Coming Soon"
BB&T visa credit
BBVA Compass Visa
Cabela's Club Visa (Spink10)
Capital One GM (General Motors) MasterCard (kilcher)
Capital One Sony Visa (SheepNutz)
Chase - IHG CC (tyler23)
Chase (MasterCard)
Chase Amazon Rewards Visa (dilutedq)
Chase Business (bmms8)
Chase Southwest Airlines Business Plus Visa
Citi - at&t Universal
Citi Dividend (MrPoopyPants)
CitiBusiness AADvantage
Credit One Bank MasterCard
Discover (dilutedq)
FIA Fidelity American Express
Fidelity Investments 529 College Rewards American Express (eimeria)
Fidelity Investments American Express
Fidelity Investments Visa (kevvyc)
First Commonwealth Federal Credit Union (Pennsylvania) (No ETA)
First Interstate Bank (mtcowdog)
First Merit (codemonkey812)
First Niagara (Coming by the end of the year)
HSBC Credit Card
Huntington National Bank Debit MasterCard
Huntington National Bank VOICE Credit MasterCard
JC Pennies Visa
KeyBank MasterCard
M&T Bank Visa (conshok26)
Macy's Credit Card (nheilweil)
Milestone Mastercard
Mountain America Credit Union - Vista Debit or Visa Credit Card (Orlandoech)
Navy Federal ["Later this Fall"] (Krevnik) November per e-mail from NFCU (oddnendz)
North Carolina State Employees Credit
Nordstrom Visa Credit Card
PayPal Mastercard (TWO2SEVEN)
Peoples United Bank (chhhrrriiisss)
Playstation Visa (Capital One says not eligible, no ETA) [devsfan1830]
Pre Paid Visa
Provident Bank
PNC Bank ["Later this Fall"] (GmDude66)
Regions Bank - Coming soon (Lifesuxbad)
Sam's Club Mastercard
San Diego County Credit Union VISA Classic (hyperliteg4)
State Farm Bank Visa (kilcher)
Target (Lloydbm41)
Toys R Us Mastercard
USAA Mastercard[Due Nov 7th] (Lloydbm41) USAA AMEX at a later date (oddnendz)
U.S. Airways Dividend Miles
U.S. Bank (piratep)
Visa MetaBank Gift Card from giftcardmall (T-Will)
Vox Business Visa through Astoria Bank (Goldnose)
VyStar Credit Union