Mobile App Sizing

[PhineasT]

I need to design a mobile app that could be accessed using multiple device types/sizes.

Screen sizes 750 x 1334 to 1170 x 2532

Does anyone have any recommendations or guidance on how to best set up screen/app sizes (height/width) and how to best set the following with the above in mind?

[Pstork1]

Your best choice is to follow the recommendations in the documentation on building a responsive app.  Building responsive canvas apps - Power Apps | Microsoft Docs