NEW YORK (CBSNewYork) — Get ready to toss your debit card out of your wallet, because soon, all you’ll need to get cash from an ATM is your smartphone.

As CBS2’s Alex Denis reported, the latest innovation in mobile technology has sparked both excitement and worry.

Bart Johnson, a customer at Wintrust Bank in Chicago, got cash from an ATM without swiping any card or entering any PIN at all.

“We go ahead and go into the mobile app ,” said Tom Ormseth, Senior Vice President of Wintrust.

As the bank demonstrated in its YouTube video, customers can order their withdrawals in advance from the convenience of their office or home.

“Pick that I want to do cardless cash. Pick the amount that I want. Pick save,” said Ormseth as he demonstrated how to use the app.

Demonstrating what to do at the ATM, Ormseth continued: “Push on cardless cash. Scan the QR code. Tells you to take your cash. Remove the bills,” Ormseth said, demonstrating what to do at the ATM.

“I like the app. If I don’t have my wallet or debit card on me but I do have my phone which I always have go right to the ATM, put it up to ATM and get my money,” said Johnson.

Ormseth said the advantage is that there is security.

The biggest security threat the app eliminates is skimming — when thieves attach a device to an ATM so that when you swipe a customer’s card, they can steal a debit number and PIN.

“There’s no card present, so skimmers can’t get the card number,” he said.

But Louis McHugh, computer systems manager at Illinois Institute of Technology, emphasized that there could still be problems.

“What if you lose that phone?” he said.

That is the question security experts raise about any kind of mobile banking, adding that even if the phone has a password, it’s not 100 percent secure.

“If somebody wants in the phone bad enough, it just takes time,” McHugh said.

McHugh also raised concerns that the Wintrust app stores banking information in the cloud.

“As we’ve seen with some of the recent security breaches, how secure is the cloud really,” wondered McHugh.

However, Ormseth argues that even if hackers steal your numbers from the cloud, they can’t get cash from the ATM without your phone.

“If it isn’t coming from the right phone, it’s not going to work,” said Ormseth.

Cardless ATMs are now available at hundreds of bank branches in several states, and they are expected to grow even more in number by the end of the year.

The entire transaction can take just 15 seconds.