The vast majority of Android and iOS apps show risky behavior, mainly driven by third-party advertising networks, according to two reports on the mobile software ecosystem published this week.
In an analysis of the top 100 paid and top 100 free apps on both iOS and Android, security firm Appthority found that free apps continued to exhibit risky behavior more often than paid apps. Collectively, 95 percent of the top 200 free apps—100 on iOS and 100 on Android—performed at least one risky behavior, such as tracking location, sharing data with advertising networks or identifying the user or user's device, according to the company's Winter 2014 App Reputation Report. While paid apps appear to be less risky than free apps, 80 percent still show risky behavior, Domingo Guerra, co-founder and president of Appthority, told eWEEK.
"We have to be more cautious users and refuse to install apps that collect too much data," he said. "There is no reason for these apps to be collecting a lot of this data."
A second report found that users are also more at risk from malicious apps on the Google Play store. RiskIQ, a security intelligence firm, found that four times as many malicious Android apps made it onto the Google Play store in 2013, compared with the number that did so in 2011. At the same time, Google removed fewer of the apps:23 percent in 2013, compared with 60 percent in 2011, the firm claims. Apps for personalizing Android phones top the lists of categories that were most likely to be malicious, the company said.
"Customers and consumers should be careful when downloading mobile apps and make every effort to vet them as being legitimate," Elias Manousos, CEO of RiskIQ, said in response to an email query from eWEEK. "Companies should invest in new security services that continuously monitor app stores, Websites and advertisements for malware."
While the number of malicious apps is growing, the threat of infection continues to be low—estimates of the proportion of infected phones in North America range from a fraction of a percent to 4 percent. Apps exhibiting risky behavior, however, are much more common.
Paying for an application is no guarantee that the developer is any more ethical than someone creating a free app, Appthority's Guerra said. More than a quarter of paid apps shared information with ad networks and analytics companies, 41 percent identified the users, and 22 percent accessed the user's address book, the company found.
"Some folks think, 'As long as I pay for an app, no one will track me,' but, no, the developers still track the users and sell that information," Guerra said.
One bright spot: Fewer of the applications in the top 100 categories, 3 percent on both iOS and Android, requested access to the calendar. Guerra theorized that complaints to developers resulted in that functionality being removed.
Yet, Appthority's definition of risky behavior includes a broad spectrum of activities. Because companies and individuals have different tolerances for risk, many of the categories might not strike the typical mobile user as dangerous. Appthority, for example, considers single sign-on technologies as potential risks because the compromise of one account can allow an attacker access to many other accounts. Depending on the mobile user, or their company policy, such functionality may or may not be considered risky, he said.
"It's now much more about the behaviors and less about a risk score," Guerra said. "A lot of companies tried to block all apps ... but now have moved to notifying the users when apps exhibit specific behaviors and reminding them not to share their calendars or their address books, for example."