The mobile phone is too complex for users to feel comfortable using them to buy physical goods, however, consumers in the U.S. and the U.K., say they are likely to use the phone to check prices and the location of a store, according to research conducted by Gartner . The report said in addition to complexity, the second-biggest reason not to shop on the phone is fear of having their location tracked. Gartner: "Retailers and wireless providers will need to clearly state the benefits that consumers gain by divulging their locations — and that their information is secure and kept private. As with loyalty cards, consumers are willing to allow retailers to collect information about them and their purchases in exchange for a discount." Still, despite these limitations, there seemed to be an opportunity—20 percent of respondents in the U.S. and 16 percent in the U.K. said they would be willing to receive promotions on their mobile phones. Based on a survey conducted among 2,000 consumers last summer, the report found: -- 32 percent of U.S. and 33 percent of U.K. respondents said complexity of using a mobile phone would be a significant barrier. -- U.S. respondents (ages 18 to 27) were 1.98 times more likely to shop on the mobile phone than respondents (ages 43 to 61). In the U.K., the younger age group was 2.63 times more likely than their older counterparts. -- Service charges for using the mobile phone as a shopping tool were not a concern in the U.S., but the fourth-largest concern in the U.K. Of course everyone is hoping the U.S. and U.K. will develop into a market similar to Japan's. Even though a small percentage of overall retail sales are conducted on mobile phones in Japan, in 2006, it totaled 562 billion yen, or $5.3 billion (that excludes content such as ringtones or games). Of this figure, 258 billion yen, or $2.4 billion, was for retail goods. The rest was for transactions and services such as purchasing tickets through a mobile phone.