"The explosive growth of mobile apps has attracted a criminal element looking for new ways to distribute malware that can be used to commit fraud, [commit] identity theft, and steal confidential data," said Manousos, in announcing the findings. Malicious apps are an effective way to infect users, he said, since they often exploit the trust people have in brands and companies they do business with.
But while the number of malicious Android apps is rising, the percentage of them removed by Google is on the decline, researchers said. In 2011 Google removed 60 percent of malicious apps, but in 2013 the company removed less than a quarter of them, the report said. That's probably due to the rapid increase in malicious software. Manousos told InfoWorld that he theorizes that Google takes down apps only after it has received enought complaints or alerts from security researchers, creating a delay in its takedowns to the 2013 surge. Unlike Apple, Google does not vet apps rigorously before they are made available in its app store, he noted.
Google said it would need more information about RiskIQ's analysis to comment on the findings.
Zach Miners covers social networking, search and general technology news for IDG News Service. Follow Zach on Twitter at @zachminers. Zach's e-mail address is email@example.com. InfoWorld executive editor Galen Gruman contributed to this report.