I'm going to create an app for iOS, Android and Windows Phone that will expose the same features that is currently available from our website which is currently being re-developed, and one of the main feature is a search feature. The website along with all the layers are all built with .net (4.5.2) and sql server and we need to expose all the services to be consumed by the mobile apps. The good thing is that it's up to me to decide how they should be exposed, but I'm not sure what's the best technology/protocol to use. What I've been told it should meet is performance/responsiveness. I thought about exposing the services as a WebAPI layer but I'm not sure if it's the best way to achieve such a requirement.
What would you recommend? Does anybody have bone through a situation like this?