iOS camera and terrain size

I'm making a fixed camera iPhone and iPad game. 3D isometric view. I wanted to know if anyone has any recommended camera sizes/angles, as well as optimal terrain size in order to fit to the iPhone screen.

Another question would be... if I wanted a flat plane to exactly take up the space of an iPhone or iPad's screen. I've looked around on the forums, but have not found any guides or solutions to help fit scenes to iOS device screens yet. I'm asking about flat planes as well for use with NGui.

Thanks in advance for your time, Bryan.