Android apk build can install but won't start

I was creating an Android app with Unity 2D engine.
The apk file was put into an Android phone and installed properly.
However when starting the app, it just stuck on a black screen, even “Powered by Unity” did not show up.

I am sure that all the scenes were chosen and the installation process did not pop any error. I think it was some sorts of setting problems… ?

If you are not using the latest version of Unity, and the Android version of your phone is old, this can happen. Fix: upgrade Unity.

you can use logcat

click here