WhatsApp has been supporting the so-called multi-device beta for some time, which is an optional program according to the messenger belonging to Facebook or Meta, which offers early access to a new WhatsApp version for web, desktop and portal. In this beta, linked companion devices can be used without a smartphone having to stay connected.
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That makes a stand-alone app for the desktop much more interesting and it is probably no coincidence that WhatsApp is now releasing a (completely) new version. This application called WhatsApp Beta and available in the Microsoft Store is a UWP app, i.e. one that is based on the Universal Windows Platform. This is intended for Windows 11 and Windows 10 and has been rewritten from scratch.
Not comparable with the previous Windows client
At this point it must of course be mentioned that there is already a desktop client for Windows. However, the previous version is nothing more than a wrapper for the browser interface. This means that this application is not only functionally limited, but above all also slow.

The new app, on the other hand, is based on UWP and apparently uses the XAML UI language, so Meta / Facebook wants to align itself with the look of current applications for Windows 10 and Windows 11. The new app, which has been officially launched as a beta so far, also enables new features, above all support for Windows Ink, i.e. pen input.
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You can now use WhatsApp on PC & tablets without a mobile phone
You can use it to draw a quick sketch with a stylus, for example, and send the image directly via Messenger. In addition, the WhatsApp UWP app will also offer functions such as backup, native notifications, options for customizing the chat and a lot more.