App icon not being set, it is always showing default green android icon

Have you changed in manifest file?

android:icon="@mipmap/ic_launcher" to

android:icon="@mipmap/your_app_logo_name"

In the manifest:

    android:icon="@drawable/ic_launcher"
    android:logo="@drawable/ic_launcher"

In the drawable folder, I added my logo named ic_launcher having size 192*192 pixels.

This solution set me on the right track.

Rename icon file to any other name in all folders & change it in menifest.xml as well.

If it was ic_launcher, change it to any other name say app_icon in folders & menifest.xml as well.

Uninstall app & install it again.

Hope will help.