I have an embedded device that runs WinCE with wireless capabilites.
I'm looking for advice on technologies I can successfully use that will allow me to easily create a web service on the WinCE device and be able to serve content to my iOS device.
I'd prefer that the web service running on the WinCE device support REST as opposed to SOAP.
A REST Web Service can really be created with anything that can listen and respond to HTTP requests, so a simple socket listener could effectively fulfill your requirements. Service over wireless and the fact that the client is iOS is actually irrelevant, as the service simply has to know how to respond to HTTP requests, probably (though not certainly) on port 80. If a PC can consume the service, so can iOS, Linux, Andoid, OD/2 or anything else. That's the whole point of a web service.
I assume, however, that you're after something a bit more feature-rich than just rolling your own socket listener. Windows CE has an optional HTTP server that can serve up basic HTML as well as a subset of classic (i.e. 3.0) ASP and some ISAPI. They all tend to be painful to use and debug, but they are included in your OS license and therefore essentially free.
There is also at least one commercial solution that I'm aware of, and that's the Padarn web server. It uses a subset of the IIS object model, so you can easily create IHttpHandlers for URIs and handle requests with compact framework assemblies. As full disclosure, I'm the creator and purveyor of Padarn, so I'm obviously biased toward it.
