On the Visual Assets tab, you set the characteristics of your app’s tile and splash screen, as well as artwork used in a number of other contexts.
Customizing the Splash Screen
To ensure that every app’s splash screen can be displayed practically instantaneously (before your app even gets loaded), you have little control over it. You specify an image (although the dimensions are different for phone versus PC) plus two optional larger sizes to support high DPI screens, and a background color for the splash screen. That’s it. Visual Studio gives you an appropriately sized placeholder
SplashScreen.scale-100.png file in an Assets subfolder, intentionally made ugly to practically guarantee you won’t forget to change it before submitting ...