How to turn off Verizon's 'supercookie' tracking

Q: How do I shut off Verizon Wireless's "supercookie" tracking?

A: Almost two months after saying it would let customers opt out of this advertising scheme, the nation's largest wireless carrier updated its privacy settings a few days ago to make that possible. You should take advantage of the opportunity immediately.

To stop the carrier from attaching a tracking header to most of your Web traffic, visit www.vzw.com/myprivacy, log into your account, and scroll down to "Relevant Mobile Advertising." Then click the button below "No, I don't want to participate in Relevant Mobile Advertising" for each line on your account and click the red "Save Changes" button below that.

You can also use this page to decline two other Verizon data-collection programs that aren't as intrusive; remember to click the separate "Save Changes" button below each.

Verizon suggests two other ways to opt out of its Web tracking: Use the My Verizon app it preloads on some mobile devices, or call 866-211-0874.

If you then visit one of the sites set up to warn Verizon customers that the carrier was stapling that identifying header to their Web use — for example, amibeingtracked.com, run by the digital-rights group Access — you should get an all-clear, but not right away.

Verizon's frequently asked page says this "Unique Identifier Header" ("UIDH" for short") will continue to appear for "a short period of time" after you opt out. Verizon spokeswoman Debra Lewis said that wait should not run longer than a week or so, adding that "in many cases it may be quicker."

You may better know this header as a "supercookie" or "permacookie," although neither of those unflattering nicknames nor the Verizon-approved monikers "Unique Identifier Header" or "UIDH" appear on that privacy-settings page.

This practice came to light last fall, after privacy advocates noticed coverage of it at such trade-news sites as Advertising Age and AdExchanger and called out two problems.

One was that you couldn't decline it — the only escape was by using encrypted Web connections, such as those offered at financial institutions and most Web-mail sites. The other was that the operator of any other site, even one not participating in Verizon's Relevant Mobile Advertising program, could use that to track you personally.

Worse, as the Electronic Frontier Foundation's Jacob Hoffman-Andrews noted in a post last November, they could combine that tracking with such older Web technologies as cookies to build a profile of you that would persist even as Verizon changed the randomly-generated header assigned to your traffic.

At the time, AT&T had been conducting its own experiment with a similar Web-tracking scheme, but it offered subscribers an opt-out and ended the entire project in November. Sprint and T-Mobile, meanwhile, had done no such thing.

A lot of privacy-scare stories turn out to be more nuanced than they first seem. This doesn't strike me as one of them. Here we have a company trying to turn its paying customers into a product to be sold to advertisers — at a non-trivial cost to their privacy, and without even some offsetting reward like that offered in Verizon Wireless's separate "Verizon Selects" program.

It's your job as a customer to express your disapproval of this one-sided practice (see also Lenovo and its even worse, since-scrapped "Superfish" Web-ads program) by opting out. Please do it now.

Tip: Stretch battery life automatically in Android 5.0 Lollipop

The 5.0 Lollipop version of Google's Android operating system hides a handy battery-saver option that can prolong your phone's usable life in the field — but only if you activate it first.

To have Android use this new "Battery Saver" mode, open the Settings app, select Battery, tap the menu button (the column of three dots), and tap "Battery saver. There, you can choose to have it activate automatically at either 5% or 15% battery; I picked 5%.

You'll know Battery Saver is active from the orange banners it puts at the top and bottom of the screen, the delayed pace of updates to your email and other apps, generally slower performance, and (hopefully!) the extra hour or more of battery life.

Rob Pegoraro is a tech writer based out of Washington, D.C. To submit a tech question, e-mail Rob at rob@robpegoraro.com. Follow him on Twitter at twitter.com/robpegoraro.