If you regularly use multiple phones and are a WhatsApp user, you are probably not happy that you cannot use the same account on different devices. WhatsApp “launches” a feature called “companion mode” for beta users, which allows the creation and use of the same WhatsApp account on four devices simultaneously.
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The new WhatsApp feature is available in beta version 2.22.24.18 and has only been rolled out to a select number of users for now. If you have the latest beta installed on your Android phone, you will be able to see the option to connect devices in the three-dot menu located in the top right corner.
The feature is not available on iPhone phones – at least for now, although it may be launched soon.

Companion mode, a feature that allows multiple phones to be connected to a single WhatsApp account, was first tested in a previous beta version of the app. The feature is now available on both tablets and phones. It's worth noting that this feature has long been available on the desktop of WhatsApp.
Being able to access WhatsApp on multiple devices has its advantages – including never losing messages or files .
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Even though the Companion Mode of WhatsApp is still in beta, it is gradually becoming available to more users. This means that a broader release is likely to happen soon.
If you want to try out WhatsApp's newest features before they're released to the general public, you can sign up for WhatsApp beta. Beta testing is a way for developers to get feedback on their apps from real users before releasing the final product.
Information source: mashable.com
