WhatsApp is trying a new service that will allow people to send messages without using their phone for the first time.
Currently, WhatsApp is connected to the user's phone. The desktop and web desktop software require the device to be connected and receive messages.
But the new service will allow users to send and receive messages "even if your phone's battery is dead".
Until four other devices - such as desktops and tablets - can be used together, WhatsApp said.
First, the new service will be offered as a "small group of users", and the team plans to improve performance and increase service before enabling everyone.
A communication system that involves people communicating to send and receive messages is an integral part of WhatsApp - and will still work under this new system, it said.
Several other messaging apps already have similar services, as well as token of the encrypted malware, which requires a sign-up phone, but not to exchange messages.
But the service has long been requested by WhatsApp users - who are reported to be two billion.
'Thinking Again'
In a blog post announcing the move, Facebook engineers said the changes needed to "rethink" the structure of the WhatsApp app.
That's because the current version "uses the smartphone app as a basic device, making the phone a source of authenticity for all user data and the only device that can send messages to someone else", the company said.
WhatsApp and other non-smartphone apps are a "mirror" of what is happening on the phone.
But the system has serious problems known to many casual users, as the web application is known for cutting off frequent communication.
It also means that only one so-called "friend app" can work at a time - so uploading WhatsApp to another device will cut the WhatsApp web window.
"The new architecture of WhatsApp devices removes these barriers, no longer need a smart phone to be a source of truth, while still keeping users' data in a safe and secure environment," the company said
On the technical side, the solution was to give each device its own "key", and WhatsApp keeps a record of which keys belong to the same user account. That means it does not need to store messages on its own server, which can lead to privacy concerns.
But Jake Moore, a security expert at the anti-virus company-Eset, said that no matter how secure security is, having a message on most devices can still be a concern.
"Abusers would now be able to use this new service to their advantage, by creating additional facilities to capture someone else's personal communication."
He also said that social networking engineering is a "growing" threat, and the responsibility lies with the user to avoid misuse.
"It is therefore important that people are aware of all the devices that are connected to their account," he warned.
