creating a login system using xcode?

I'm trying to create an iPhone app using xcode, and I want to know if I can authenticate users remotely using https i.e

• user enters their username and password
• send the v开发者_如何学JAVAariables to a php file
• and gets the results back!

I know how to sort everything out in terms of php, but in the xcode side I'm really stuck!

You might want to start here. Also doing a google search on example https code and security in iphone sdk will surface quite a number of links and tutorials.