Anonymous app Whisper denies tracking claims
IMAGE: Neetzan Zimmerman, Whisper editor »
The Guardian newspaper claims Whisper has an in-house tool which can track the locations of all its users.
This includes some who have specifically opted out of sharing location details, the report claims.
Whisper editor Neetzan Zimmerman tweeted that the article was "riddled with outright lies and made-up quotes".
The Guardian also claimed the app was tracking "newsworthy" posters and was sharing data with the US Department of Defense in instances where secrets were uploaded from military bases.
"We are not sharing specific user data with any organisation," wrote Mr Zimmerman in response.
"We noticed how frequently suicide is mentioned among those living on US military bases or compounds and reached out to organisations to see how we could work together to address this important issue."
However, he added that "violent or child-endangering threats" were reported to law enforcement agents "to protect our users and the public".
"We comply with the legal process in all instances," he wrote.
"We respond to both subpoenas and preservation requests from law enforcement. Whisper is not a place for illegal activity."
Two journalists from the newspaper had visited Whisper's offices in the US to explore a working relationship, which the Guardian says it will no longer pursue due to concerns over user privacy.
The Guardian has been contacted by the BBC for comment.
News and community site Buzzfeed has also announced it is "taking a break" from its partnership with the platform following the report.
"We're taking a break from our partnership until Whisper clarifies to us and its users the policy on user location and privacy," it said in a statement.
Behind the scenes
Millions of "secrets" - a short sentence written over a picture - have been shared via the social media platform since its launch two years ago.
"You look at all of these services like Facebook and Instagram, and they're all about, 'Let me show you the best version of me,'" Whisper co-founder Michael Heyward told the BBC earlier this year.
"Whisper is about showing people the behind-the-scenes stuff that we're not always comfortable posting on Facebook."
In his response to the Guardian's report, Neetzan Zimmerman added that the firm did not store geographical data or any other information which might identify a user.
"There is nothing in our geolocation data that can be tied to an individual user and a user's anonymity is never compromised," he wrote.
"Even for users who opt into geolocation services, the location information that we do store is obscured to within 500m of their smartphone device's actual location.
"Whisper does not follow or track users. Whisper does not request or store any personally identifiable information from users, therefore there is never a breach of anonymity."
Article Credit: BBC