Control the user interface on all iPhones with various zoom / resolution

Question

What is the best approach for handling iPhone4, iPhone5, iPhone6, iPhone6 ​​+ UI screens in iOS?

• Size for iPhone 6+ with @ 3x scaling, coordinate space: 414 x 736 pixels.
• Size for iPhone 6 with @ 2x scaling, coordinate space: 375 x 667 pixels.

Answer 1

I think this question has already been answered here.

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