WASHINGTON – AT&T and Verizon have been using “supercookies” to track more than 100 million cellphone users.

These “supercookies” make it so you can’t simply go into your browser settings and choose “private” or “incognito” modes. Even the savvy users are finding it hard to escape the cookies, The Washington Post reports.

The cookies have allowed Verizon and AT&T to monitor the sites you visit and keep track of your tastes and interests.

The companies say they’ve taken steps to let customers know about the tracking.

The Electronic Frontier Foundation, a civil liberties group, is considering legal action against Verizon. AT&T’s pilot program isn’t as advanced and is in testing, according to the company.

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