It makes the UI elements maintain their original size. so they remain the same size even if the resolution changes and then we can use "Best Fit" for Text component which will make it appear better on the screen.
You can set your Canvas' "UI Scale Mode" under "Canvas Scaler" to "constant physical size"
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Top Swift interview Questions And Answers for Freshers
What are best practices that you use when developing projects in Objective-C ?