How to create Universal apps in iPhone/iPad?

I want to create a universal apps. I have already done some apps for iPhone. Now i want to start a universal apps which means the app should be runs in iPhone and iPad. I don't have any idea about开发者_如何学运维 that. So please guide me and give me some sample links for that.

Thanks!

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It's easier than you'd think.

If UI is your only difference, you just need to have different XIBs for each platform. Then you configure in plist files, which XIB you'd load on each platform.

This link helped me a lot http://www.weston-fl.com/blog/?p=563