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I would like to create an iphone app for certain websites:

how easy/hard is this ?
As easy/hard as simple/complex you decide to make the app, taking into account how much skill/talent you have in the coding, etc. required.

You could just create a iPhone-friendly, mobile version of this website (probably easier) or you could build a native app for it (probably harder). And, most importantly, you need to either own or have permission to repurpose the site. You do, right?
 
Yes

This is my cousin and he contacted me to do this.

How much do you think something like this would cost me ?
 
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