How do I optimize gameplay for iPhone 5 and up? I know for Windows 8 apps that the ideal screen size/dimensions is 1366 x 768 so what are the right dimensions for iPhones so that the picture isn't distorted?
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It's not really about the layout size but the ratio. Fronne explained how to cover issue with various screen ratios on mobile devices here https://www.scirra.com/tutorials/1126/m ... le-devices.
If you want it only for the iPhone 5 and up, you can calculate ratio based on the Apple's devices official specs... there not that much devices with iOS.