We're developing an iOS app for the coal industry which will perform several calculations.
We need 5 buttons designed for the main menu, one for each function: Conversion Calculator, Blending Calculator, Logistics Calculator, Price Calculator, and Project Feasibility Calculator.
The buttons/icons will be arranged in a 2048w x1536h (ipad 3 screen dimensions). We are thinking the background color of the page will be grey. We think the icon/button should represent the function graphically (example: a truck for the transportation, a dollar sign for the calculator, etc).
ideally the buttons/icons will be modular enough that we can arrange the icons on the screen freely (for example, top to bottom, pentagon, or one in center followed by 2x2 columns)
Please see attached for a color scheme/sample icons that we like.