This post has been updated since it was originally published.

Update:T-Mobile confirmed that it also uses Carrier IQ to measure metrics for network performance.

“T-Mobile does not use this diagnostic tool to obtain the content of text, email or voice messages, or the specific destinations of a customers’ internet activity, nor is the tool used for marketing purposes,” said Troy Edwards, a spokesman for T-Mobile in a statement.

Original post:Wireless carriers and handset makers have slowly been clarifying how they use Carrier IQ, the software program that can record information from cellphones. Carrier IQ’s program is meant to collect user data to “assist operators and device manufacturers in delivering high-quality products and services to their customers.” But the average user can’t see or agree to this data collection, which is what’s caused such outrage.

Verizon spokesman Jeffrey Nelson said on his Twitter account that the company does not use Carrier IQ on its phones.

AT&T and Sprint have both released statements saying that they use Carrier IQ for network monitoring and maintenance purposes. “In-line with our privacy policy, we solely use CIQ software data to improve wireless network and service performance,” said AT&T spokesman Mark Siegel.

Sprint, the carrier that was featured in security researcher Troy Eckhart’s videos showing the program’s activities, also said that it uses the program to monitor connection problems, but does not and cannot look at or record the contents of text messages.

“Carrier IQ provides information that allows Sprint, and other major carriers that use it, to analyze our network performance and identify where we should be improving service,” said Sprint spokeswoman Stephanie Vinge-Walsh. She added that the company uses the program to figure out connection or other issues on the network and the information is never sold.

“The Sprint privacy policy makes it clear we collect information that includes how a device is functioning and how it is being used,” she said in a statement. “Carrier IQ is an integral part of the Sprint service. Sprint relies on Carrier IQ to help maintain our network performance.”

Handset manufacturer Nokia issued a statement to the Verge saying that it does not install the program on its phones. The Verge also reported that the program is not present on Google-branded devices such as the Google Nexus line of phones.

In a statement, Apple said that it has supported the program in the past but has stopped using it “in most” of its products. The company also said that customers can opt not to send any Carrier IQ data by choosing not to share diagnostic data and that it will remove the program completely in future updates, GigaOm reported.

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