WhatsApp seems to be developing a multi-device WhatsApp feature that allows users to send chats to the same account, on different smartphones or tablets.
This information was first revealed by WABetaInfo, through the screen display of the Beta version of the WhatsApp application.
The screen display shows instructions for registering the device used as a secondary device (a device other than the primary smartphone) by scanning the code from the primary phone.
Quoting The Verge, Friday (4/29/2022), a screenshot that is suspected to be a beta display of WhatsApp shows that different devices can have the ability to sync messages and still be protected by end-to-end encryption.
The screen above, coupled with the “Register Device as Companion” which instructs users on how to use WhatsApp on other devices, adds to the evidence that this feature is being developed by WhatsApp.
Both screens are found on the Android version of the WhatsApp application. That means, the feature will support chat on a secondary device or tablet.
It's not clear at this time whether the feature will also be available on the iOS version of WhatsApp and when it might be released.
For your information, WhatsApp now supports the use of accounts on multi-device through the new Linked Device feature that supports use on computers as secondary devices. This WhatsApp multi-device feature is already available on iOS and Android.
WhatsApp previously rolled out the Linked Device multi-device feature as a public beta feature in November 2021. This feature continues to be developed after its release, although there are still some features that are not supported, depending on the main device used.
Although Linked Devices is quite helpful for desktop users, currently the multi-device feature cannot be used on a smartphone or tablet as a secondary device.
Unfortunately, WhatsApp's parent, Meta, also did not provide an answer when asked about plans to expand the Linked Devices feature to support use on mobile devices.