Facebook on Sunday denied it has been logging Android users' call and text history without their permission.
While some users' information is logged, the social media company said the function "has always been opt-in only." When the feature is enabled, it allows Facebook to see when a call or text was sent or received, the company said.
"You may have seen some recent reports that Facebook has been logging people's call and SMS (text) history without their permission. This is not the case," Facebook said in a statement. "People have to expressly agree to use this feature."
Ars Technica reported Saturday that some Facebook users had discovered years' worth of phone call metadata in their downloadable Facebook data file. Facebook requests access to phone-contact data to improve its friend-recommendation algorithm, the site reported.
"Call and text history logging is part of an opt-in feature for people using Messenger. While we receive certain permissions from Android, uploading this information has always been opt-in only," Facebook said.
Facebook said that the feature doesn't collect the contents of calls or texts, and that the information collected isn't sold to third parties.
The social media giant has been embroiled in afor the past week after reports of a data analytics firm that worked for the Donald Trump campaign misusing Facebook users' personal information during the 2016 US election. Cambridge Analytica is accused of exploiting the personal data of 50 million of Facebook users and using the information to manipulate US voters in the presidential campaign.
Cambridge Analytica has denied using the information for the Trump campaign.
On Sunday, Facebook CEOin newspapers including The New York Times and The Wall Street Journal to apologize. "This was a breach of trust, and I'm sorry we didn't do more at the time. We're now taking steps to ensure this doesn't happen again," Zuckerberg wrote.
The ads appeared the same day that Reuters published the results of a poll that found fewer than half the Americans surveyed -- 41 percent -- trust Facebook to obey US privacy laws. That compared with 66 percent who said they trust Amazon, 62 percent who trust Google, 60 percent for Microsoft and 47 percent for Yahoo.
Originally published March 25 at 3:15 p.m. PT.
Updated March 26 at 6:41 a.m. PT: Added background information.
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