Scaling according to phone dimensions

Greetings guys, I need help on mobile platform porting. I am currently using phoneGap. It appears that there are size issues due to project scaling. What is the appropriate way to do this?

It works well for iPad dimensions as the images for my project are of 768x1024. However, in iPhone it is scaled automatically by C2 export using fullscreen in browser [On] in my project settings. After exporting, there are white borders in the canvans because the images are not scaled to the correct iPhone size.

This tutorial has good information about screens on mobile devices:

http://www.scirra.com/tutorials/73/supporting-multiple-screen-sizes

Basically, since all mobile devices have different window sizes, the scale function will work differently for every device you try on. So you need to set a background so it covers over the white borders.

Thanks Mike! I guess I have to cater for different aspect ratios.