What is the most secure way to know a secure web request is made by an iPhone

What is the most secure way for a web server to know that the request has been posted by an iPhone, and开发者_如何学Python by nothing else. (https POST request made by ASIHttpRequest).

Thanks, Niels

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There is no secure way to do this. It is relatively easy to write a client that "impersonates" an iPhone client down to the last byte of the request.