What has become one of the most popular phone apps for messaging internationally is becoming available via a web browser on the desktop (an extension). The browser version is a little odd as it needs an active phone session to operate which it then mirrors. All the messages still happen on the phone, with the desktop as an interface. Another odd quirk is that the desktop does not work with Apple iPhone, just Android, Blackberry and Windows. The company is blaming Apple limitations for the lack of the new service.
To get the app to work with your browser, go to web.whatsapp.com in your Google Chrome browser. Scan the QR code with your phone running the latest Whatsapp version and you can start using the web desktop front-end. Not a great solution but something users can begin to utilize as the company blocks some third party applications that were accesses the service without permission.
How to use Whatsapp on your PC/Browser!