SAN FRANCISCO (CN) - Apple didn't warn that its new Wi-Fi Assist app automatically switches iPhones from wireless to cellular data, causing some users to exceed data limits and pay higher phone bills, customers claim in a federal class action.
Lead plaintiffs William and Suzanne Phillips sued Apple on Friday, seeking punitive damages for negligent misrepresentation, unfair competition and false advertising.
The lawsuit zeroes in on the iPhone's Wi-Fi Assist app's default setting in its latest operating system, which makes phones switch to using cellular data when nearby Wi-Fi signals are weak.
The lawsuit cites articles in Fortune.com and The Washington Post, warning customers about the risk of the default setting "eating up" their data plans.
The Phillipses say Apple failed to issue a statement about the data-depleting application until after a "flood of articles" appeared on the subject.
"Because you'll stay connected to the Internet over cellular when you have a poor Wi-Fi connection, you might use more cellular data," Apple stated in an Oct. 2 announcement about the app. "For most users, this should only be a small percentage higher than previous usage."
The announcement informed iPhone users they could disable Wi-Fi Assist through their phone's cellular data settings.
But the plaintiffs say this Apple's attempt to correct the problem by issuing that statement fell short, and that it downplays the data overcharges users may incur.
"Defendant's corrective statement does not disclose any basis for its conclusion that an average consumer would not see much increase in cellular usage," the 14-page complaint states.
When the Phillipses upgraded their iPhones' to the latest operating system, iOS 9, they had no idea the upgrade would cause their phones to silently start using cellular data and jack up their phone bills, they say.
They seek class certification and statutory, compensatory and punitive damages.
They are represented by Michael McShane, with Audet & Partners in San Francisco.
Apple declined to comment Monday.
Apple's iPhone accounted for 44.2 percent of the U.S. smartphone market in July, far ahead of second-place Samsung's 28.6 percent, according to data analysis company comScore. But the Android operating still rules Apple, by 52.2 percent to Apple's iOS 44.2 percent, according to comScore.
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