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I have downloaded Open Sans font and added all the .tff files into my Xcode project, and have checked the checkbox in "Target Membership" pane for each file. I have added the UIAppFontskey and values in Info.plist, and I am sure that the values are typo-free. Plus, the .tff files are added to "Copy Bundle Resources", and the custom font is showing up in Interface Builder. And then I changed the font of all the labels to Open Sans in the Interface Builder (no code).But when I run the app in the simulator, all the labels and buttons are showing the system font in ultra small sizes, like this:(picture)One thing to note is that I am using Xcode 7 beta 5, and the app's Base SDK is iOS 9.But why is there this problem? Is it a bug? Thanks!