Britons are using their mobiles to spend more than £250m a year just on eBay, sharpening questions over the security available on the devices.
The online shopping and auction site reported this week that customers used mobiles to complete 10% of its sales, or some two million deals, in August alone.
In 2010 global mobile-based sales more than trebled to $2bn, and could double again this year, the firm said. In the UK, 170,000 shoppers were using the eBay mobile app to spend an average of £30 a week, bringing UK mobile sales to around £265m.
eBay does not normally disclose the value of trades, but it said the most expensive items sold in each of the two months were top-end cars. In July it was a Ferrari F430 Spider F1 for more than £70,000, while in August it was a Bentley Continental GTC Auto for more than £50,000.
eBay added someone had gone through eBay to buy a house in the south of France in July.
These sums have attracted cybercriminals. Mobile reported the number of hacked phones almost trebled in a year, but the number is still low compared to PCs.
The European cybersecurity agency Enisa said cybercriminals are using app stores to distribute malware that they could use to steal bank and credit card details or re-route purchases to addresses they control. It has called for app store owners to adopt a five-level defence against malware.
Men were twice more likely than women to use their mobiles to buy stuff on eBay. One-fifth of mobile shoppers were aged between 26 and 30, but over 50s were more active shoppers than under 20s, eBay said.