In the Wizard grid app tiles are getting colors because they are referring to images that are present in the asset folder.
If you observe DataModel/SampleDataSource.CS in the constructor(SampleDataSource()) they are creating sample data item objects whose fourth parameter is the path of the image for that particular item. Each sample data item is added to a sample data group
so you can change the colors of the tiles or you can replace them with your own images by changing the fourth parameter of the sample data item.
2. if you observe the StandardStyles.xaml present in "common" folder of the solution there is a data template "Standard250x250ItemTemplate" present there you can change the title and subtitle which is present on the tile.
3.if you observe the package.appxmanifest in the application go to applicationUI tab there you can observe the background color property. By modifying the value there you can change the splash screen color.
Thanks
Raja KPV
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