Your PWA on Android when launched shows the main color of the app on the top bar. This article explains why this occurs and how you can change this color.
You observed that when you launched your app the top bar screen (where your battery usage and date usually are) 'inherits' the main color of the app. That is, the background color for the top bar is adjusted according to your main app's color settings.
This is the default behavior for web apps on Android.
- PWA on Android device
If you wish to change the color, on your App Dashboard, Navigate to Create -> Design -> Global Styling and change the Main App Color.
If you decided to change the Main App Color, the next time you will launch your PWA on an Android device, this color will show on the top bar of your screen.