Designing for Iphone

Hi Guys,

Has anyone designed for iPhones here before?

I think the res was 320px wide by xxx px

ANyway, I designed the graphics, yet when they were uploaded onto the phone, the 320 pixel wide graphic was tiny on the screen, any ideas why? It was like it was scaled down by the phone for some reason.

I’m only designing the graphics, we have a developer putting it together, did she do something wrong somewhere or should i make the graphic bigger?