Disappearing private messages are being tested by Facebook as it experiments with a new option for those using its Messenger app. They become hidden after a set amount of time chosen by the user, according to the company.
Senders must select a device to use it on, as messages sent this way are stored on the device. Those that have the option to “disappear” will be deleted from the device.
"Starting a secret conversation with someone is optional. Secret conversations can only be read on one device, and we recognize that the experience may not be right for everyone," the company said.
Facebook cites as examples of messages people may wish to keep secret those related to health or finances – while others mentioned secret romances.
The idea is being tested on a “limited basis,” Facebook said, but added that it will be widely available over the summer. Videos and GIFs can’t be sent secretly right now. The service will also have additional features for reporting abuse — and when it does, there will be a delay in deleting messages to trigger the flag.
The service was built on the Signal protocol from Open Whisper Systems, which is widely used by messaging apps, said expert Professor Alan Woodward from the University of Surrey. “Signal is well-tested and those who developed it are considered among the best in cryptography,” he said. “But the problem with such an open standard is that if a problem arises it could have far-reaching consequences.”
Professor Woodward added that the technical report published by Facebook “was not as comprehensive as many would have liked” in terms of assessing the service’s security.
