I am building a phone application which will display a shape on screen. The shape should look the same on different screen sizes. I Decided the best way to do this is to show more of the background on larger screen keeping the shapes proportion the same on all screens.
My problem is I am not sure how to achieve this, I can query the screen size at runtime and calculate how different it is from the six is designed for but I am not sure what to do with this value.
What kind of projection should I use for my orthographic matrix an hour will I display more on larger screens and not loose information on smaller screens?
EDIT: Here is an image to help illustrate what I mean -