Let's say I have a solution involving an iPhone app that generates some information and then sends that information to a web service for processing. It is important that ONLY requests from instances of this particular iPhone app are allowed to be processed (there may be many instances of the app used by many different users, but I want to be sure they are all using code that I trust). In other words I want to be sure that my iPhone app cannot be (easily) impersonated by other clients. How would you do this?

iphone authentication
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