There has a been a web client for WhatsApp that users could sync with their mobile app by scanning a bar code on their browser with their phone on which an active WhatsApp account is, but now there is a desktop app that can be downloaded for Windows 8+ and Mac OS 10.9+ PCs.
Just like the WhatsApp Web, the app mirrors your phone and requires that your phone has an internet connection to work on your PC.
We would like to see a situation where the WhatsApp account one registers on the desktop app works independently of the mobile app, so that even if the phone has blacked out, one can still access WhatsApp messages on desktop. If security is a concern, there could be a provision for app lock on the desktop version, so that users can create a code or password to open and view messages, reducing the fear that someone else using one’s PC can read messages.
Just a thought, Mark 🙂