A study of US phone users has predicted an increase in mobile fraud as a result of the increased smartphone market and mobile transactions. It mirrors the growth of online fraud which accompanied the growth of the internet.
The study was carried out by fraud detection technology company 41st Parameter … so I suppose you could argue that they would say it was increasing. However the study does raise some important points:

With the growth of the smartphone market, the online fraud prevention methods are less effective
The multiplicity of mobile operating systems makes fraud prevention more difficult
The growth of dedicated mobile sites, especially in the banking sector, has seen a similar growth in phishing sites. These are less obvious to users than the more familiar web sites, where people tend to be naturally suspicious of phishing

Although mobile presents new problems for fraud management, it also gives some specific solutions. Additional forms of verification are available on the mobile through the phone number and geo location.

A copy of the report can be ordered through the 41st Parameter website.