How to set game scene according to iPad and iPhone for 2D game in Unity4.3

Hi,
I am new in Unity. I am going to develop 2D game, before that I need to know that how can I set game scene for both iPhone and iPad. I am much curios about sizing of images and orientation of screen because I don’t know this. I already set game scene for iPad but this was done by hit and try. I don’t know exactly to set game scene according to device. Kindly suggest me on this. Thanks in advance.

You can tell the platform the game is running on using Application.Platform.

You can determine the screen resolution, width, and height, from Screen.currentResolution, Screen.width, and Screen.height.