Since it’s acquisition by Facebook there have been several improvements in the way people communicate on Whatsapp.
Read a Review of Whatsapp vs BBM
Whatsapp launched the web version of the whatsapp on the computer. And now you can access whatsapp on your computer through the link http://web.whatsapp.com. To access that you need to have Google Chrome browser on your computer.
However the messages are all time both on the smartphone app just like the the web browser.
Only android users will be able to access the whatsapp on the web browser.