Slow startup time on Android

There are already a few older threads about this, but there doesn't seem to be a solution.

Under Android, every app using Vuforia takes at least 10-12 seconds from the splash screen until the app appears. Tested on reasonably fast mid-end phones (e.g. Pocofone, Snapdragon 845 with 2.8Ghz).

This also happens in the Vuforia samples.

The worst thing about this is that there is just a blank screen during that time. Assuming nothing can be done about the delay, is there at least a way to display a loading screen or something? (This may be more of a Unity question than Vuforia question).

How could i debug where the actual delay happens? If i take a look at the Android system log, the last output before the delay is the GPU capabilities, then 10-12 seconds nothing, then the next line is "Vuforia initialized". So i assume the delay is somewhere in Vuforia?

Thanks for any hints.