Consumers are worried that being able to pay for items with just a tap of their smartphone will lead to them making more impulse purchases.
Apple Pay - the feature that will enable iPhone 6 users to buy things just by touching their smartphone to a contactless card point - is set to launch in the UK this month, but a quarter of people asked told a new survey that they were concerned the quick and easy method will see them make more impulse buys.
The survey of more than 1,200 UK adults was carried out by comparison website uSwitch.com and also found that, despite concerns, the brand power of Apple made more than a quarter (26%) feel more comfortable using the technology.
The mobile payment technology is known as near-field communication (NFC), and has been available in some Samsung phones for more than two years, while Apple Pay launched in the US last year and comes to the UK for the first time this month.
Security was also raised as a potential concern, with 45% saying it was their biggest worry over using the technology, and 38% said they would like a cap on tap-and-go payments in order to curb their spending.
Apple Pay is set to come with such a limit, with single transactions set to be limited to £20 when it launches this month. One in 10 said they thought restricting use of mobile payments in pubs and clubs would help them spend less.
USwitch.com money expert Nicholas Frankcom said: "It's great to see people being given more options on how to pay. This is a clear case of how technology can make people's lives easier.
"If they can use these tools to help keep track of their money, that's an added bonus. However, using your mobile to pay could be a double-edged sword.
"If paying with your phone is so simple that we don't think about whether or not we can afford it, it could lead to debt problems.
"New technology should be welcomed, but it's equally important that consumers use it to help them take control of their finances, not lose it."
The average UK household now owns 18 smart devices such as mobile phones and tablets and spends more than £100 a year on downloads, according to a survey by Samsung.