Long white screen before application start on device

Ionic Framework ionic-v3
1

Hi all ! Could anyone suggest why always before application start on device we can see long white screen nearly15 seconds ?

2

If The Splahscreen not shown make this :
ionic platform rm android
ionic platform add android@latest
ionic resources
if the Splahscreen show good and the app is slow to start you can build your app with --prod:
ionic build anroid --prod

3

@aboessa, your instructions helped. Thanks!

4

aboessa, thx a lot, all working right.