I’m working on a .NET CF PDA app that communicates with a Ruby on Rails web app. With .NET CF emulator you have to connect to ActiveSync so it can connect to the development server. I couldn’t work out why the RoR server was going down everytime I tried to debug the PDA app. Eventually I tracked it down to the fact that ActiveSync and the RoR server were using the same port – port 3000. Now I can run debuggers on the PDA and web apps at the same time, which is pretty cool. I haven’t yet worked out how to get the emulator to connect to the internet without ActiveSync.