Whisper immediately fired back that The Guardian's story was full of "lousy falsehoods," and that it does not collect or store any personally identifiable information from users, insisting its service is completely anonymous.
The Guardian has since responded, reiterating that Whisper does collect users' smartphone ID codes, their IP data, and, if people turn on their geolocation services, their location within 500 meters.
So, what kinds of things are people sharing on Whisper anyway?