Yes it can, but it should not be done. The "splash" screen is shown when you app is being loaded in memory. You can delay the remove all of this screen bij not return directly form the application:didFinishLaunchingWithOptions:
method. But doing so might get your app killed by the os because it is take to long to load.
You best option to place a view in the UIWindow
that show that your app is downloading data. This way your user see that your app is doing something. If it is possible to show some kind of progress here that would even be better.
You could even do it in the view controller where you perform the network call, just push a loading view onto the view just before you start the netwerk call. Once it is finished remove the view. This will work only if the network call is not blocking any UI updates.