Are 'Imposter' Apps Taking Over Your Smartphone? . / Credit: Smartphone texting image via Shutterstock

Many Americans are putting their personal data at risk by downloading "imposter" apps, new research finds.

Consumer Reports found that 39 percent of the more than 100 million Americans who own a smartphone do not take any measures to protect those devices. Those measures include simple things like using a screen lock, backing up data or having an app to locate missing devices or wipe data.

The researchers found that as a result of that inaction, 7.1 million smartphones were damaged, lost or stolen in 2012. An additional 5.6 million smartphones were victims of malicious software attacks, including unauthorized text messages or unauthorized account access.

Many people use their smartphones for both personal and business reasons — which presents a unique set of challenges and dangers to smartphone users. However, Consumer Reports recommended a number of steps people can take to guard their smartphones.

First and foremost, smartphone owners should use a strong passcode to keep their devices and information safe. Consumer Reports said codes with a mixture of letters and numbers are better than traditional four-digit codes, which can be cracked with the right software.

Additionally, the researchers said smartphone users must avoid downloading malicious apps. In 2012, 1.6 million smartphone owners downloaded applications that were imposters of well-known apps. [8 Android Trojans You Need to Watch Out For]

Consumer Reports also warned smartphone users to be especially careful when using unsecured Wi-Fi networks, as they can allow criminals to easily steal data from users.

Smartphone users should also be sure to turn off location-tracking, except when it is necessary, Consumer Reports said. Indeed, 1 percent of smartphone users said they had been harassed by someone who was able to track their location through their smartphone.

"When you take your smartphone into your confidence, so to speak, you're also taking in a host of parties, including app developers, your wireless carrier and phone manufacturer, mobile advertisers, and the maker of your phone's operating system," said Jeff Fox , technology editor at Consumer Reports. "We recommend that all smartphone users take the basic precautions we outline in this report to ensure that their phones are secure from wireless threats."

The research was based on the responses of more than 3,000 adults as a part of the Consumer Reports State of the Net survey.

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