C# projects and GUI

Hi there,

I am developing an application that requires instant voice (and may be video) messaging on smart devices using .NET CF. I heard that VOIP will provide excellent way for this. However, does anyone have any open source application done using VOIP in CF

The other concern is that smart devices have limited resources in memory, still I have seen some people developing smart device application with very good interface and icons. I don't know whether they are using a specific format that has very short size or not.

So please if anyone has any idea about any of these two concerns, let me know

Regards

Salman