Although WhatsApp users can use messaging across multiple platforms, a smartphone connection is still required, in large part due to the way WhatsApp handles the issue of end-to-end encryption (E2EE).
This is about to change and eventually the user will no longer need to have a mobile phone around to use WhatsApp on the web, macOS, Windows or Portal.
From now on, WhatsApp will ask users to try the beta phase on multiple devices. It is possible to use the service on your mobile phone and on up to four other devices (as long as they are not mobile phones as well). WhatsApp will test the cross-device approach with a small group of people from its beta program. They will be able to disable the beta later. With the help of these users, WhatsApp will streamline the experience across multiple devices and add a few more features before deploying it more widely.
Although many users requested support for multiple devices, WhatsApp took some time for this to happen. He’s built a system that maintains end-to-end encryption while allowing people to sync data like contact names, files and starred messages between devices.
Until now, the WhatsApp smartphone app has been an essential channel for the service. Other platforms, such as the web and desktop apps, maintain a consistent and secure link to the mobile app and mirror the content. But if your phone battery runs out or there is a problem with the smartphone app, it becomes impossible to use WhatsApp on other platforms.
By testing on multiple devices, each device will have its own identity key. Currently, users have a unique identity key (ie the one on their mobile phones) to handle encrypted messages. WhatsApp has developed systems that will keep snoopers out trying to add devices to a user’s account and minimize the number of times people need to confirm their identity on the devices. The user will also have control over the connected devices and will see which ones are linked to his account.
Along with messaging, WhatsApp will have E2EE support for voice and video calls as part of testing across multiple devices. There will be no impact on how WhatsApp handles cloud backups.
Solving the problem of supporting E2EE on a user’s devices can be tricky since only the devices to and from which messages are sent must be able to decrypt them. Apple seems to have found an answer – iMessage supports E2EE on all Apple devices. Although Telegram works across multiple devices, its E2EE (Secret Chats) approach does not currently do so. As with the current WhatsApp setup, Signal’s desktop app also needs to connect to a smartphone to send and receive messages.