However, it’s still a wireless carrier, making it capable of baffling decisions. T-Mobile is informing customers who starting on April 26 that they will automatically be opted into a program that shares their web and mobile app data with advertisers (via MacRumors).

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The data-sharing partnership is quite similar to one at Sprint prior to its purchase by T-Mobile, but it required customers to deliberately opt-in. The intention of the program, according to a T-Mobile spokesperson, is to deliver more relevant ads to customers, something which they indicate customers expressed a preference for.  While I have no doubt customers are interested in more relevant ads, whether it’s an exchange they are willing to make for their privacy might be another matter. While the customers’ names won’t be attached to the data, it will include unique identifiers and, according to Electronic Frontier Foundation lawyer Aaron Mackey, it is “trivial to link to that unidentified data back to you.”  Verizon and AT&T both opt customers into a similar program, but it pools customer data prior to sharing it with advertisers rather than giving unique identifiers. Both networks then have separate programs customers can choose to opt into that provides more of their data to advertisers. 

How to opt out of T-Mobile’s new data sharing

If you would prefer not to have your data shared with advertisers as part of this new program, opting out is quite simple. Opting out on the T-Mobile website:

Navigate to the T-Mobile website (opens in new tab)Click on My Account in the upper-right cornerSelect Profile, Privacy and NotificationsClick Advertising & AnalyticsTurn off Use my data to make ads more relevant to me

Opting out in the T-Mobile app:

Open the T-Mobile appTap on the More tabSelect Advertising & AnalyticsTurn off Use my data to make ads more relevant to me