Cant make Newtonsoft.Json to work

im having folowing code and setup

http://pastebin.com/XikdKHFt

http://pastebin.com/01jDQDyA

now as you can see from screenshot i'm having problems with WebClient as it says that this name does not exist in the current context, now the same code works in Test3.Android MainActivity. My guess is that this error comes from lack of components. I'm new to crossplatform so i'm still learning and hoping someone here can tell me a way around.