A mother has warned parents to be vigilant after her eight-year-old daughter spent £1,450 playing iPad games online.
Katie Phillips' daughter reset security settings to accept her own fingerprint to make purchases.
The girl from Wrexham, who Ms Phillips has not named, spent the sum in just three days.
A Barclaycard spokesperson said they empathised but Ms Phillips would have to pay.
Ms Phillips' daughter made 255 purchases, ranging from 99p to £19.99, on the game-making app Roblox, despite the gadget being password-protected - managing to bypass the password to use her fingerprint as the default payment method.
She racked up a debt of £1,890 and, after Barclaycard agreed not to charge interest on the transactions, the bill was reduced to £1,450.
Her iPad has been confiscated and she has been banned from using iTunes games as punishment.
Ms Phillips, 35, said: "I felt sick and was in floods of tears. I was so shocked, disappointed and annoyed.
"It was hard to be too angry with her because she didn't really know what she was doing and she didn't understand.
"We are really angry, but she is innocent. She said she thought it was free.
"She does look sorry. She looked white when we spoke to her about it and she started crying.
"But she just doesn't realise how much money she spent and what that means."
Ms Phillips bought her daughter the £300 seventh generation iPad for Christmas.
Despite fearing she was too young, she relented as the eight-year-old wanted to design and play games with her friends.
She disabled in-game chat functions, barred social media and set up a child-friendly account.
"The iPad was her dream present. She had no idea what the password was," Ms Phillips said.
Ms Phillips only realised what had happened when she received an email from Barclaycard saying she had a credit card payment due - even though the balance should have been £0.
She said: "I thought it must have been fraud at first. But then I saw the transactions were all from Apple and I just thought 'oh my god'.
Ms Phillips and her husband Matty tried to get money back from Barclaycard and Apple but, because the card wasn't used for fraud, they fear they are unlikely to succeed.
She said: "We have been left with that figure and we are going to have to pay it by the looks of things.
"Other parents have got to be so careful. I thought I was being careful but obviously not careful enough. Children are clever and you have to be very vigilant.
"I think there needs to be more measures put in place to stop things like from happening.
"There are clearly flaws in the system. No-one should be able to make that amount of transactions in one day.
"I was not contacted at all by the bank about the spending, which I feel was excessive and should have raised concerns."
A Barclaycard spokesperson said: "We are sorry that Ms Phillips has had cause to complain.
"Unfortunately, customers are liable for the transactions authorised using their Apple ID, and we are therefore unable to provide a refund.
"However, we empathise with Ms Phillips' situation, so we have made arrangements not to charge any interest on the transactions.
"Apple has a range of features to help parents control spending on their devices, such as the ability to switch off in-app purchases, and we would encourage all customers to make use of them."
Apple have also been contacted for a statement.