Splash screens on updated Google apps turn into a place for the company to push its brand
YouTube splash screen
In its Material Design guidelines, Google notes that branded splash screens are a good way to promote a brand while an app is loading. You wouldn't think that Google would feel threatened; but in the fast paced world of providing apps and cloud storage, a strong brand now could find itself struggling down the road.
"Branded launch screens are a good way to portray a brand while the app is loading. Take advantage of the loading time to display your logo or other elements that improve brand recognition. Avoid using text on this screen except your logo and, if applicable, a tagline."-from Google's Material Design guidelines
source: Forbes
Things that are NOT allowed: