WhatsApp will no longer be supported on Windows Phone 8.0 after December 31, 2017. This means that if you are currently using WhatsApp on a Windows Phone 8.0, you will be able to continue to use WhatsApp on that phone before this date. However, as part of this process, it will not be possible to create a WhatsApp account on a Windows Phone 8.0, nor move an existing WhatsApp account to a Windows Phone 8.0 after November 1, 2017.
Most Windows Phone 8.0 devices can be upgraded to Windows Phone 8.1. For instructions on doing this, read the following Microsoft Support page.
As announced in our blog, WhatsApp is not supported on Windows Phone 7. This means that if you are currently using Windows Phone 7, you will not be able to use WhatsApp on that phone.