Using your phone camera insted of your laptop camera

Hello everyone,

I’m developing an application with server and client interface.
The application should replace the laptop camera with an usb connected phone camera.

I’m just at the beginning and I need help.
What should I know and which website are important ?
I have no idea how I can start.

At the end, my application should work like the Droid cam application.

So I will be very happy i someone gives me a hit where can I start and what need to do first.