Apple's iTunes gift card are no longer just a last-minute kids gift idea. They have become an important part of modern day scams.

A 74-year-old Melbourne woman has been swindled out of $46,000 by scammers who groomed her to buy 330 iTunes gift cards as part of their crime.

But police say the woman would have lost a lot more money if a suspicious retailer hadn't contacted police.

The Hawthorn woman was called by an unknown man in mid-July claiming to be from a major telecommunications company. He maintained contact with her for a week and then asked her to withdraw cash and buy iTunes gift-card codes.

The criminal also hacked into the woman's computer and internet banking, telling her he had deposited money in her account to "fix her security problem".

The man insisted that she relay the iTunes gift codes over the phone as well as send cash using Moneygram.

"The offenders made transfers of cash between the victim's three bank accounts in order to confuse her and make it look like the balance of her account was increasing," Detective Senior Constable Cameron Mitchell of the Yarra Crime Investigation Unit said. 

"The victim believed she was transferring the telco's money to the overseas accounts when in fact it was her own."

Detective Senior Constable Cameron said the retail worker noticed how many cards the woman was buying and how much money she was carrying and they contacted police. He described the attack as cruel and targeted.

"It has been a traumatic experience for the victim and there is a message everyone can take from this."

"We are trying to get the message out to potential victims but also to retailers. If it wasn't for that store intervening, this could have been much worse."

This type of scam is called "phishing". It describes conning people by pretending to be from a well known company or government agency. 

In June 2017, the Australian Consumer and Competition Commission received more than 11,000 reports of phishing scams, with nearly $260,000 lost.

Tech giant Apple's website warns users against the iTunes scam. 

"Regardless of the reason for payment, the scam follows a certain formula: The victim receives a call instilling panic and urgency to make a payment by purchasing iTunes Gift Cards from the nearest retailer," the warning reads.

"After the cards have been purchased, the victim is asked to pay by sharing the 16-digit code on the back of the card with the caller over the phone.

"Please do not ever provide the numbers on the back of the card to someone you do not know."