Currently I am delivering ad hoc versions for testing, and later on I will be submitting the application to the store. I have added all the required icons in "AppIcon" in "Images.xcassets". Now while installing the app through the iTunes, the app icon is missing. I found that I need to add a 512x512 png named "iTunesArtwork" in the root folder to get this fixed up.
But referring to the doc https://developer.apple.com/LIBRARY/IOS/qa/qa1686/_index.html, It say that for applications to be submitted on store we don't need to add the "iTunesArtwork".
So does that mean for store applications filling all the icons in "Images.xcassets" is enough to get app icons at all the places, (spotlight, searches, home screen icon, and also the iTunes app section) ?
You need to add the artwork when you fill in the metadata in iTunes connect. You will also need to upload screenshots.