When I try to run my app on Iphone X simulator, I noticed there are some odd spaces on top and bottom of the screen as shown in the the image below.
When I try to query the height and width of the screens, it shows 375 x 667, which is not correct for Iphone X.
Anyone knows how to solve this issue?
It may have to do with the XCode version/settings you’re using. According to the Apple documentation, full screen apps are enabled only under certain conditions, and it may be possible that your app is working in some “compatibility” mode that adds safe margins.
Bruno
(I know you asked this 4 months ago, but I am facing similar issues today and thought it may be useful for other users too 
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