Mobile phone technology has evolved a lot in the last five years, with apps virtually for everything.
But some of these apps contain hidden risks.
"If you suddenly find that your device seems to be sending texts that you didn't send, or emails that you didn't send, that means your device essentially has been captured by the spyware or the malware," according to Leonard Gordon, NE Director of the Federal Trade Commission.
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Once downloaded, the FTC warns that some apps have unfettered access to a wide range of privacy-invasive information like your location, activities, interests, and even friends. First they collect the data, then they share it.
"One of the big issues that's being discussed right now is how much tracking is done to determine what ads you see," said Gordon.
So how do you know if your phone is at risk?
According the App Genome Project, Apple has more than 340,000 apps available now, compared to nearly 90,000 apps available on Android. But because of Android’s looser approval policies, more of the suspicious apps hit Android phones.
But that doesn't mean your iPhone is immune.
Nicolas Seriot, a Swiss researcher, authored a white paper indicting that a design flaw in Apple's app review process is allowing rogue apps that could be hidden within an innocent-looking app, such as a game.
It happened already. The game app storm8 was sued in 2009 for allegedly harvesting customer phone numbers without permission, but it later stopped that practice.
Apple representatives did not respond to e-mails seeking comment.
The FTC recommends that users should download apps from companies they are familiar with, and read the reviews.
"If someone is doing malicious things, most likely they're doing it to more than one person, so the word is going to get out pretty quickly," says app user Todd Nathanson.
If app stores are notified, they'll usually create security patches in the next software update.